Science.gov

Sample records for environment electron transport

  1. A Deterministic Transport Code for Space Environment Electrons

    NASA Technical Reports Server (NTRS)

    Nealy, John E.; Chang, C. K.; Norman, Ryan B.; Blattnig, Steve R.; Badavi, Francis F.; Adamczyk, Anne M.

    2010-01-01

    A deterministic computational procedure has been developed to describe transport of space environment electrons in various shield media. This code is an upgrade and extension of an earlier electron code. Whereas the former code was formulated on the basis of parametric functions derived from limited laboratory data, the present code utilizes well established theoretical representations to describe the relevant interactions and transport processes. The shield material specification has been made more general, as have the pertinent cross sections. A combined mean free path and average trajectory approach has been used in the transport formalism. Comparisons with Monte Carlo calculations are presented.

  2. A Deterministic Computational Procedure for Space Environment Electron Transport

    NASA Technical Reports Server (NTRS)

    Nealy, John E.; Chang, C. K.; Norman, Ryan B.; Blattnig, Steve R.; Badavi, Francis F.; Adamcyk, Anne M.

    2010-01-01

    A deterministic computational procedure for describing the transport of electrons in condensed media is formulated to simulate the effects and exposures from spectral distributions typical of electrons trapped in planetary magnetic fields. The primary purpose for developing the procedure is to provide a means of rapidly performing numerous repetitive transport calculations essential for electron radiation exposure assessments for complex space structures. The present code utilizes well-established theoretical representations to describe the relevant interactions and transport processes. A combined mean free path and average trajectory approach is used in the transport formalism. For typical space environment spectra, several favorable comparisons with Monte Carlo calculations are made which have indicated that accuracy is not compromised at the expense of the computational speed.

  3. Transport of Space Environment Electrons: A Simplified Rapid-Analysis Computational Procedure

    NASA Technical Reports Server (NTRS)

    Nealy, John E.; Anderson, Brooke M.; Cucinotta, Francis A.; Wilson, John W.; Katz, Robert; Chang, C. K.

    2002-01-01

    A computational procedure for describing transport of electrons in condensed media has been formulated for application to effects and exposures from spectral distributions typical of electrons trapped in planetary magnetic fields. The procedure is based on earlier parameterizations established from numerous electron beam experiments. New parameterizations have been derived that logically extend the domain of application to low molecular weight (high hydrogen content) materials and higher energies (approximately 50 MeV). The production and transport of high energy photons (bremsstrahlung) generated in the electron transport processes have also been modeled using tabulated values of photon production cross sections. A primary purpose for developing the procedure has been to provide a means for rapidly performing numerous repetitive calculations essential for electron radiation exposure assessments for complex space structures. Several favorable comparisons have been made with previous calculations for typical space environment spectra, which have indicated that accuracy has not been substantially compromised at the expense of computational speed.

  4. Nonequilibrium electron transport in a hybrid superconductor-normal metal entangler in a dissipative environment

    NASA Astrophysics Data System (ADS)

    Bubanja, Vladimir; Yamamoto, Mayumi; Iwabuchi, Shuichi

    2016-11-01

    We consider a three-terminal Cooper-pair splitting device with a superconducting electrode tunnel coupled to two normal metal electrodes. We employ the Nambu-Gor'kov and Schwinger-Keldysh formalisms to describe the nonequilibrium transport properties of the device for arbitrary transmissions of the barriers and for a general electromagnetic environment. We derive the analytic expressions for the current and the nonlocal differential conductance, and analyze the limits of clean and dirty superconductivity.

  5. Electronics for Extreme Environments

    NASA Technical Reports Server (NTRS)

    Patel, J. U.; Cressler, J.; Li, Y.; Niu, G.

    2001-01-01

    Most of the NASA missions involve extreme environments comprising radiation and low or high temperatures. Current practice of providing friendly ambient operating environment to electronics costs considerable power and mass (for shielding). Immediate missions such as the Europa orbiter and lander and Mars landers require the electronics to perform reliably in extreme conditions during the most critical part of the mission. Some other missions planned in the future also involve substantial surface activity in terms of measurements, sample collection, penetration through ice and crust and the analysis of samples. Thus it is extremely critical to develop electronics that could reliably operate under extreme space environments. Silicon On Insulator (SOI) technology is an extremely attractive candidate for NASA's future low power and high speed electronic systems because it offers increased transconductance, decreased sub-threshold slope, reduced short channel effects, elimination of kink effect, enhanced low field mobility, and immunity from radiation induced latch-up. A common belief that semiconductor devices function better at low temperatures is generally true for bulk devices but it does not hold true for deep sub-micron SOI CMOS devices with microscopic device features of 0.25 micrometers and smaller. Various temperature sensitive device parameters and device characteristics have recently been reported in the literature. Behavior of state of the art technology devices under such conditions needs to be evaluated in order to determine possible modifications in the device design for better performance and survivability under extreme environments. Here, we present a unique approach of developing electronics for extreme environments to benefit future NASA missions as described above. This will also benefit other long transit/life time missions such as the solar sail and planetary outposts in which electronics is out open in the unshielded space at the ambient space

  6. An environment-dependent semi-empirical tight binding model suitable for electron transport in bulk metals, metal alloys, metallic interfaces, and metallic nanostructures. I. Model and validation

    SciTech Connect

    Hegde, Ganesh Povolotskyi, Michael; Kubis, Tillmann; Klimeck, Gerhard; Boykin, Timothy

    2014-03-28

    Semi-empirical Tight Binding (TB) is known to be a scalable and accurate atomistic representation for electron transport for realistically extended nano-scaled semiconductor devices that might contain millions of atoms. In this paper, an environment-aware and transferable TB model suitable for electronic structure and transport simulations in technologically relevant metals, metallic alloys, metal nanostructures, and metallic interface systems are described. Part I of this paper describes the development and validation of the new TB model. The new model incorporates intra-atomic diagonal and off-diagonal elements for implicit self-consistency and greater transferability across bonding environments. The dependence of the on-site energies on strain has been obtained by appealing to the Moments Theorem that links closed electron paths in the system to energy moments of angular momentum resolved local density of states obtained ab initio. The model matches self-consistent density functional theory electronic structure results for bulk face centered cubic metals with and without strain, metallic alloys, metallic interfaces, and metallic nanostructures with high accuracy and can be used in predictive electronic structure and transport problems in metallic systems at realistically extended length scales.

  7. An environment-dependent semi-empirical tight binding model suitable for electron transport in bulk metals, metal alloys, metallic interfaces, and metallic nanostructures. I. Model and validation

    NASA Astrophysics Data System (ADS)

    Hegde, Ganesh; Povolotskyi, Michael; Kubis, Tillmann; Boykin, Timothy; Klimeck, Gerhard

    2014-03-01

    Semi-empirical Tight Binding (TB) is known to be a scalable and accurate atomistic representation for electron transport for realistically extended nano-scaled semiconductor devices that might contain millions of atoms. In this paper, an environment-aware and transferable TB model suitable for electronic structure and transport simulations in technologically relevant metals, metallic alloys, metal nanostructures, and metallic interface systems are described. Part I of this paper describes the development and validation of the new TB model. The new model incorporates intra-atomic diagonal and off-diagonal elements for implicit self-consistency and greater transferability across bonding environments. The dependence of the on-site energies on strain has been obtained by appealing to the Moments Theorem that links closed electron paths in the system to energy moments of angular momentum resolved local density of states obtained ab initio. The model matches self-consistent density functional theory electronic structure results for bulk face centered cubic metals with and without strain, metallic alloys, metallic interfaces, and metallic nanostructures with high accuracy and can be used in predictive electronic structure and transport problems in metallic systems at realistically extended length scales.

  8. Electron transporting semiconducting polymers in organic electronics.

    PubMed

    Zhao, Xingang; Zhan, Xiaowei

    2011-07-01

    Significant progress has been achieved in the preparation of semiconducting polymers over the past two decades, and successful commercial devices based on them are slowly beginning to enter the market. However, most of the conjugated polymers are hole transporting, or p-type, semiconductors that have seen a dramatic rise in performance over the last decade. Much less attention has been devoted to electron transporting, or n-type, materials that have lagged behind their p-type counterparts. Organic electron transporting materials are essential for the fabrication of organic p-n junctions, organic photovoltaic cells (OPVs), n-channel organic field-effect transistors (OFETs), organic light-emitting diodes (OLEDs) and complementary logic circuits. In this critical review we focus upon recent developments in several classes of electron transporting semiconducting polymers used in OLEDs, OFETs and OPVs, and survey and analyze what is currently known concerning electron transporting semiconductor architecture, electronic structure, and device performance relationships (87 references).

  9. The influence of leaf anatomy on the internal light environment and photosynthetic electron transport rate: exploration with a new leaf ray tracing model

    PubMed Central

    Xiao, Yi; Tholen, Danny; Zhu, Xin-Guang

    2016-01-01

    Leaf photosynthesis is determined by biochemical properties and anatomical features. Here we developed a three-dimensional leaf model that can be used to evaluate the internal light environment of a leaf and its implications for whole-leaf electron transport rates (J). This model includes (i) the basic components of a leaf, such as the epidermis, palisade and spongy tissues, as well as the physical dimensions and arrangements of cell walls, vacuoles and chloroplasts; and (ii) an efficient forward ray-tracing algorithm, predicting the internal light environment for light of wavelengths between 400 and 2500nm. We studied the influence of leaf anatomy and ambient light on internal light conditions and J. The results show that (i) different chloroplasts can experience drastically different light conditions, even when they are located at the same distance from the leaf surface; (ii) bundle sheath extensions, which are strips of parenchyma, collenchyma or sclerenchyma cells connecting the vascular bundles with the epidermis, can influence photosynthetic light-use efficiency of leaves; and (iii) chloroplast positioning can also influence the light-use efficiency of leaves. Mechanisms underlying leaf internal light heterogeneity and implications of the heterogeneity for photoprotection and for the convexity of the light response curves are discussed. PMID:27702991

  10. The influence of leaf anatomy on the internal light environment and photosynthetic electron transport rate: exploration with a new leaf ray tracing model.

    PubMed

    Xiao, Yi; Tholen, Danny; Zhu, Xin-Guang

    2016-11-01

    Leaf photosynthesis is determined by biochemical properties and anatomical features. Here we developed a three-dimensional leaf model that can be used to evaluate the internal light environment of a leaf and its implications for whole-leaf electron transport rates (J). This model includes (i) the basic components of a leaf, such as the epidermis, palisade and spongy tissues, as well as the physical dimensions and arrangements of cell walls, vacuoles and chloroplasts; and (ii) an efficient forward ray-tracing algorithm, predicting the internal light environment for light of wavelengths between 400 and 2500nm. We studied the influence of leaf anatomy and ambient light on internal light conditions and J The results show that (i) different chloroplasts can experience drastically different light conditions, even when they are located at the same distance from the leaf surface; (ii) bundle sheath extensions, which are strips of parenchyma, collenchyma or sclerenchyma cells connecting the vascular bundles with the epidermis, can influence photosynthetic light-use efficiency of leaves; and (iii) chloroplast positioning can also influence the light-use efficiency of leaves. Mechanisms underlying leaf internal light heterogeneity and implications of the heterogeneity for photoprotection and for the convexity of the light response curves are discussed.

  11. Electronic transport in polycrystalline graphene.

    PubMed

    Yazyev, Oleg V; Louie, Steven G

    2010-10-01

    Most materials in available macroscopic quantities are polycrystalline. Graphene, a recently discovered two-dimensional form of carbon with strong potential for replacing silicon in future electronics, is no exception. There is growing evidence of the polycrystalline nature of graphene samples obtained using various techniques. Grain boundaries, intrinsic topological defects of polycrystalline materials, are expected to markedly alter the electronic transport in graphene. Here, we develop a theory of charge carrier transmission through grain boundaries composed of a periodic array of dislocations in graphene based on the momentum conservation principle. Depending on the grain-boundary structure we find two distinct transport behaviours--either high transparency, or perfect reflection of charge carriers over remarkably large energy ranges. First-principles quantum transport calculations are used to verify and further investigate this striking behaviour. Our study sheds light on the transport properties of large-area graphene samples. Furthermore, purposeful engineering of periodic grain boundaries with tunable transport gaps would allow for controlling charge currents without the need to introduce bulk bandgaps in otherwise semimetallic graphene. The proposed approach can be regarded as a means towards building practical graphene electronics.

  12. Electron transport in bipyridinium films.

    PubMed

    Raymo, Françisco M; Alvarado, Robert J

    2004-01-01

    Bipyridinium dications are versatile building blocks for the assembly of functional materials. In particular, their reliable electrochemical response has encouraged the design of electroactive films. Diverse and elegant experimental strategies to coat metallic and semiconducting electrodes with bipyridinium compounds have, in fact, emerged over the past two decades. The resulting interfacial assemblies span from a few nanometers to several micrometers in thickness. They incorporate from a single molecular layer to large collections of entangled polymer chains. They transport electrons efficiently from the electrode surface to the film/solution interface and vice versa. Electron self-exchange between and the physical diffusion of the bipyridinium building blocks conspire in defining the charge transport properties of these fascinating electroactive assemblies. Often, the matrix of electron-deficient bipyridinium dications can be exploited to entrap electron-rich analytes. Electrostatic interactions promote the supramolecular association of the guests with the surface-confined host matrix. Furthermore, chromophoric sites can be coupled to the bipyridinium dications to produce photosensitive arrays capable of harvesting light and generating current. Thus, thorough investigations on the fundamental properties of these functional molecule-based materials can lead to promising applications in electroanalysis and solar energy conversion, while contributing to advances in the basic understanding of electron transport in interfacial assemblies.

  13. Designing Electronic Collaborative Learning Environments

    ERIC Educational Resources Information Center

    Kirschner, Paul; Strijbos, Jan-Willem; Kreijns, Karel; Beers, Pieter Jelle

    2004-01-01

    Electronic collaborative learning environments for learning and working are in vogue. Designers design them according to their own constructivist interpretations of what collaborative learning is and what it should achieve. Educators employ them with different educational approaches and in diverse situations to achieve different ends. Students use…

  14. Electron Transport in Hall Thrusters

    NASA Astrophysics Data System (ADS)

    McDonald, Michael Sean

    Despite high technological maturity and a long flight heritage, computer models of Hall thrusters remain dependent on empirical inputs and a large part of thruster development to date has been heavily experimental in nature. This empirical approach will become increasingly unsustainable as new high-power thrusters tax existing ground test facilities and more exotic thruster designs stretch and strain the boundaries of existing design experience. The fundamental obstacle preventing predictive modeling of Hall thruster plasma properties and channel erosion is the lack of a first-principles description of electron transport across the strong magnetic fields between the cathode and anode. In spite of an abundance of proposed transport mechanisms, accurate assessments of the magnitude of electron current due to any one mechanism are scarce, and comparative studies of their relative influence on a single thruster platform simply do not exist. Lacking a clear idea of what mechanism(s) are primarily responsible for transport, it is understandably difficult for the electric propulsion scientist to focus his or her theoretical and computational tools on the right targets. This work presents a primarily experimental investigation of collisional and turbulent Hall thruster electron transport mechanisms. High-speed imaging of the thruster discharge channel at tens of thousands of frames per second reveals omnipresent rotating regions of elevated light emission, identified with a rotating spoke instability. This turbulent instability has been shown through construction of an azimuthally segmented anode to drive significant cross-field electron current in the discharge channel, and suggestive evidence points to its spatial extent into the thruster near-field plume as well. Electron trajectory simulations in experimentally measured thruster electromagnetic fields indicate that binary collisional transport mechanisms are not significant in the thruster plume, and experiments

  15. Electronic transport in unconventional superconductors

    SciTech Connect

    Graf, M.J.

    1998-12-31

    The author investigates the electron transport coefficients in unconventional superconductors at low temperatures, where charge and heat transport are dominated by electron scattering from random lattice defects. He discusses the features of the pairing symmetry, Fermi surface, and excitation spectrum which are reflected in the low temperature heat transport. For temperatures {kappa}{sub B}T {approx_lt} {gamma} {much_lt} {Delta}{sub 0}, where {gamma} is the bandwidth of impurity induced Andreev states, certain eigenvalues become universal, i.e., independent of the impurity concentration and phase shift. Deep in the superconducting phase ({kappa}{sub B}T {approx_lt} {gamma}) the Wiedemann-Franz law, with Sommerfeld`s value of the Lorenz number, is recovered. He compares the results for theoretical models of unconventional superconductivity in high-{Tc} and heavy fermion superconductors with experiment. The findings show that impurities are a sensitive probe of the low-energy excitation spectrum, and that the zero-temperature limit of the transport coefficients provides an important test of the order parameter symmetry.

  16. Harsh environments electronics : downhole applications.

    SciTech Connect

    Vianco, Paul Thomas

    2011-03-01

    The development and operational sustainment of renewable (geothermal) and non-renewable (fossil fuel) energy resources will be accompanied by increasingly higher costs factors: exploration and site preparation, operational maintenance and repair. Increased government oversight in the wake of the Gulf oil spill will only add to the cost burden. It is important to understand that downhole conditions are not just about elevated temperatures. It is often construed that military electronics are exposed to the upper limit in terms of extreme service environments. Probably the harshest of all service conditions for electronics and electrical equipment are those in oil, gas, and geothermal wells. From the technology perspective, advanced materials, sensors, and microelectronics devices are benefificial to the exploration and sustainment of energy resources, especially in terms of lower costs. Besides the need for the science that creates these breakthroughs - there is also a need for sustained engineering development and testing. Downhole oil, gas, and geothermal well applications can have a wide range of environments and reliability requirements: Temperature, Pressure, Vibration, Corrosion, and Service duration. All too frequently, these conditions are not well-defifined because the application is labeled as 'high temperature'. This ambiguity is problematic when the investigation turns to new approaches for electronic packaging solutions. The objective is to develop harsh environment, electronic packaging that meets customer requirements of cost, performance, and reliability. There are a number of challenges: (1) Materials sets - solder alloys, substrate materials; (2) Manufacturing process - low to middle volumes, low defect counts, new equipment technologies; and (3) Reliability testing - requirements documents, test methods and modeling, relevant standards documents. The cost to develop and sustain renewable and non-renewable energy resources will continue to escalate

  17. Mars Transportation Environment Definition Document

    NASA Technical Reports Server (NTRS)

    Alexander, M. (Editor)

    2001-01-01

    This document provides a compilation of environments knowledge about the planet Mars. Information is divided into three catagories: (1) interplanetary space environments (environments required by the technical community to travel to and from Mars); (2) atmospheric environments (environments needed to aerocapture, aerobrake, or use aeroassist for precision trajectories down to the surface); and (3) surface environments (environments needed to have robots or explorers survive and work on the surface).

  18. Electronic Transport in Graphene Heterostructures

    NASA Astrophysics Data System (ADS)

    Young, Andrea F.; Kim, Philip

    2011-03-01

    The elementary excitations of monolayer graphene, which behave as massless Dirac particles, make it a fascinating venue in which to study relativistic quantum phenomena. One notable example is Klein tunneling, a phenomena in which electrons convert to holes to tunnel through a potential barrier. However, the omnipresence of charged impurities in substrate-supported samples keep the overall charge distribution nonuniform, obscuring much of this "Dirac" point physics in large samples. Using local gates, one can create tunable heterojunctions in graphene, isolating the contribution of small regions of the samples to transport. In this review, we give an overview of quantum transport theory and experiment on locally gated graphene heterostructures, with an emphasis on bipolar junctions.

  19. Regulation of Photosynthetic Electron Transport and Photoinhibition

    PubMed Central

    Roach, Thomas; Krieger-Liszkay, Anja Krieger

    2014-01-01

    Photosynthetic organisms and isolated photosystems are of interest for technical applications. In nature, photosynthetic electron transport has to work efficiently in contrasting environments such as shade and full sunlight at noon. Photosynthetic electron transport is regulated on many levels, starting with the energy transfer processes in antenna and ending with how reducing power is ultimately partitioned. This review starts by explaining how light energy can be dissipated or distributed by the various mechanisms of non-photochemical quenching, including thermal dissipation and state transitions, and how these processes influence photoinhibition of photosystem II (PSII). Furthermore, we will highlight the importance of the various alternative electron transport pathways, including the use of oxygen as the terminal electron acceptor and cyclic flow around photosystem I (PSI), the latter which seem particularly relevant to preventing photoinhibition of photosystem I. The control of excitation pressure in combination with the partitioning of reducing power influences the light-dependent formation of reactive oxygen species in PSII and in PSI, which may be a very important consideration to any artificial photosynthetic system or technical device using photosynthetic organisms. PMID:24678670

  20. Inner Radiation Belt Representation of the Energetic Electron Environment: Model and Data Synthesis Using the Salammbo Radiation Belt Transport Code and Los Alamos Geosynchronous and GPS Energetic Particle Data

    NASA Technical Reports Server (NTRS)

    Friedel, R. H. W.; Bourdarie, S.; Fennell, J.; Kanekal, S.; Cayton, T. E.

    2004-01-01

    The highly energetic electron environment in the inner magnetosphere (GEO inward) has received a lot of research attention in resent years, as the dynamics of relativistic electron acceleration and transport are not yet fully understood. These electrons can cause deep dielectric charging in any space hardware in the MEO to GEO region. We use a new and novel approach to obtain a global representation of the inner magnetospheric energetic electron environment, which can reproduce the absolute environment (flux) for any spacecraft orbit in that region to within a factor of 2 for the energy range of 100 KeV to 5 MeV electrons, for any levels of magnetospheric activity. We combine the extensive set of inner magnetospheric energetic electron observations available at Los Alamos with the physics based Salammbo transport code, using the data assimilation technique of "nudging". This in effect input in-situ data into the code and allows the diffusion mechanisms in the code to interpolate the data into regions and times of no data availability. We present here details of the methods used, both in the data assimilation process and in the necessary inter-calibration of the input data used. We will present sample runs of the model/data code and compare the results to test spacecraft data not used in the data assimilation process.

  1. Coordinating Electron Transport Chains to an Electron Donor.

    PubMed

    Villegas, Carmen; Wolf, Maximilian; Joly, Damien; Delgado, Juan Luis; Guldi, Dirk M; Martín, Nazario

    2015-10-16

    Two electron transport chains (2 and 3) featuring two fullerenes with different electron acceptor strengths have been synthesized, characterized, and coordinated to a light harvesting/electron donating zinc porphyrin. Electrochemical assays corroborate the redox gradients along the designed electron transport chains, and complementary absorption and fluorescence titrations prove the assembly of ZnP-2 and ZnP-3 hybrids.

  2. Electronic transport in nanoscale structures

    NASA Astrophysics Data System (ADS)

    Lagerqvist, Johan

    In this dissertation electronic transport in nanoscale structures is discussed. An expression for the shot noise, a fluctuation in current due to the discreteness of charge, is derived directly from the wave functions of a nanoscale system. Investigation of shot noise is of particular interest due to the rich fundamental physics involved. For example, the study of shot noise can provide fundamental insight on the nature of electron transport in a nanoscale junction. We report calculations of the shot noise properties of parallel wires in the regime in which the interwire distance is much smaller than the inelastic mean free path. The validity of quantized transverse momenta in a nanoscale structure and its effect on shot noise is also discussed. We theoretically propose and show the feasibility of a novel protocol for DNA sequencing based on the electronic signature of single-stranded DNA while it translocates through a nanopore. We find that the currents for the bases are sufficiently different to allow for efficient sequencing. Our estimates reveal that sequencing of an entire human genome could be done with very high accuracy in a matter of hours, e.g., orders of magnitude faster than present techniques. We also find that although the overall magnitude of the current may change dramatically with different detection conditions, the intrinsic distinguishability of the bases is not significantly affected by pore size and transverse field strength. Finally, we study the ability of water to screen charges in nanopores by using all-atom molecular dynamics simulations coupled to electrostatic calculations. Due to the short length scales of the nanopore geometry and the large local field gradient of a single ion, the energetics of transporting an ion through the pore is strongly dependent on the microscopic details of the electric field. We show that as long as the pore allows the first hydration shell to stay intact, e.g., ˜6 nearby water molecules, the electric field

  3. Electron transport in ferromagnetic nanostructures

    NASA Astrophysics Data System (ADS)

    Lee, Sungbae

    As the size of a physical system decreases toward the nanoscale, quantum mechanical effects such as the discretization of energy levels and the interactions of the electronic spins become readily observable. To understand what happens within submicrometer scale samples is one of the goals of modern condensed matter physics. Electron transport phenomena drew a lot of attention over the past two decades or so, not only because quantum corrections to the classical transport theory, but also they allow us to probe deeply into the microscopic nature of the system put to test. Although a significant amount of research was done in the past and thus extended our understanding in this field, most of these works were concentrated on simpler examples. Electron transport in strongly correlated systems is still a field that needs to be explored more thoroughly. In fact, experimental works that have been done so far to characterize coherence physics in correlated systems such as ferromagnetic metals are far from conclusive. One reason ferromagnetic samples draw such attention is that there exist correlations that lead to excitations (e.g. spin waves, domain wall motions) not present in normal metals, and these new environmental degrees of freedom can have profound effects on decoherence processes. In this thesis, three different types of magnetic samples were examined: a band ferromagnetism based metallic ferromagnet, permalloy, a III-V diluted ferromagnetic semiconductor with ferromagnetism from a hole-mediated exchange interaction, and magnetite nanocrystals and films. The first observation of time-dependent universal conductance fluctuations (TD-UCF) in permalloy is presented and our observations lead to three major conclusions. First, the cooperon contribution to the conductance is suppressed in this material. This is consistent with some theoretical expectations, and implies that weak localization will be suppressed as well. Second, we see evidence that domain wall motion

  4. Environic implications of lighter than air transportation

    NASA Technical Reports Server (NTRS)

    Horsbrugh, P.

    1975-01-01

    The advent of any new system of transportation must now be reviewed in the physical context and texture of the landscape. Henceforward, all transportation systems will be considered in respect of their effects upon the environment to ensure that they afford an environic asset as well as provide an economic benefit. The obligations which now confront the buoyancy engineers are emphasized so that they may respond to these ethical and environic urgencies simultaneously with routine technical development.

  5. Electron Transport in Short Peptide Single Molecules

    NASA Astrophysics Data System (ADS)

    Cui, Jing; Brisendine, Joseph; Ng, Fay; Nuckolls, Colin; Koder, Ronald; Venkarataman, Latha

    We present a study of the electron transport through a series of short peptides using scanning tunneling microscope-based break junction method. Our work is motivated by the need to gain a better understanding of how various levels of protein structure contribute to the remarkable capacity of proteins to transport charge in biophysical processes such as respiration and photosynthesis. We focus here on short mono, di and tri-peptides, and probe their conductance when bound to gold electrodes in a native buffer environment. We first show that these peptides can bind to gold through amine, carboxyl, thiol and methyl-sulfide termini. We then focus on two systems (glycine and alanine) and show that their conductance decays faster than alkanes terminated by the same linkers. Importantly, our results show that the peptide bond is less conductive than a sigma carbon-carbon bond. This work was supported in part by NSF-DMR 1507440.

  6. Design of an eMonitor system to transport electronic patient care report (ePCR) information in unstable MobileIP wireless environment.

    PubMed

    Giovanni, Mazza G; Shenvi, Rohit; Battles, Marcie; Orthner, Helmuth F

    2008-11-06

    The eMonitor is a component of the ePatient system; a prototype system used by emergency medical services (EMS) personnel in the field to record and transmits electronic patient care report (ePCR) information interactively. The eMonitor component allows each Mobile Data Terminal (MDT) on an unreliable Cisco MobileIP wireless network to securely send and received XML messages used to update patient information to and from the MDT before, during and after the transport of a patient.

  7. Vapor Transport to Indoor Environments

    EPA Science Inventory

    The indoor environment is an important microenvironment for human exposure to chemicals, both because people spend most of their time indoors and because chemicals are often at higher concentrations indoors versus outdoors. This chapter reviews the major components in estimating ...

  8. Coupled electron-photon radiation transport

    SciTech Connect

    Lorence, L.; Kensek, R.P.; Valdez, G.D.; Drumm, C.R.; Fan, W.C.; Powell, J.L.

    2000-01-17

    Massively-parallel computers allow detailed 3D radiation transport simulations to be performed to analyze the response of complex systems to radiation. This has been recently been demonstrated with the coupled electron-photon Monte Carlo code, ITS. To enable such calculations, the combinatorial geometry capability of ITS was improved. For greater geometrical flexibility, a version of ITS is under development that can track particles in CAD geometries. Deterministic radiation transport codes that utilize an unstructured spatial mesh are also being devised. For electron transport, the authors are investigating second-order forms of the transport equations which, when discretized, yield symmetric positive definite matrices. A novel parallelization strategy, simultaneously solving for spatial and angular unknowns, has been applied to the even- and odd-parity forms of the transport equation on a 2D unstructured spatial mesh. Another second-order form, the self-adjoint angular flux transport equation, also shows promise for electron transport.

  9. Numerical Solution of 3D Poisson-Nernst-Planck Equations Coupled with Classical Density Functional Theory for Modeling Ion and Electron Transport in a Confined Environment

    SciTech Connect

    Meng, Da; Zheng, Bin; Lin, Guang; Sushko, Maria L.

    2014-08-29

    We have developed efficient numerical algorithms for the solution of 3D steady-state Poisson-Nernst-Planck equations (PNP) with excess chemical potentials described by the classical density functional theory (cDFT). The coupled PNP equations are discretized by finite difference scheme and solved iteratively by Gummel method with relaxation. The Nernst-Planck equations are transformed into Laplace equations through the Slotboom transformation. Algebraic multigrid method is then applied to efficiently solve the Poisson equation and the transformed Nernst-Planck equations. A novel strategy for calculating excess chemical potentials through fast Fourier transforms is proposed which reduces computational complexity from O(N2) to O(NlogN) where N is the number of grid points. Integrals involving Dirac delta function are evaluated directly by coordinate transformation which yields more accurate result compared to applying numerical quadrature to an approximated delta function. Numerical results for ion and electron transport in solid electrolyte for Li ion batteries are shown to be in good agreement with the experimental data and the results from previous studies.

  10. MUCH Electronic Publishing Environment: Principles and Practices.

    ERIC Educational Resources Information Center

    Min, Zheng; Rada, Roy

    1994-01-01

    Discusses the electronic publishing system called Many Using and Creating Hypermedia (MUCH). The MUCH system supports collaborative authoring; reuse; formatting and printing; management; hypermedia publishing and delivery; and interchange. This article examines electronic publishing environments; the MUCH environment; publishing activities; and…

  11. Electron Transport in Water Vapour

    NASA Astrophysics Data System (ADS)

    Kawaguchi, Satoru; Satoh, Kohki; Itoh, Hidenori

    2015-09-01

    Sets of electron collision cross sections for water vapour previously reported are examined by comparing calculated electron swarm parameters with measured parameters. Further, reliable cross section set of water vapour is estimated by the electron swarm method using Monte Carlo simulation to ensure the accuracy of the swarm parameter calculation. The values of an electron drift velocity, a longitudinal diffusion coefficient, and an effective ionisation coefficient calculated from Yousfi and Benabdessadok's set and those calculated from Itikawa and Mason's set do not necessarily agree with measured data. A new cross section set of water vapour, which consists of three kinds of rotational excitation, two kinds of vibrational excitation, three kinds of electron attachment, twenty-six kinds of electronic excitation, and six kinds of ionisation cross sections, and an elastic collision cross section, is estimated, and an anisotropic electron scattering for elastic and rotational excitation collision is considered. The swarm parameters calculated from the estimated cross section set is in good agreement with measured data in a wide range of reduced electric field.

  12. [Transport, environment and health. 2008 SESPAS Report].

    PubMed

    Ballester, Ferran; Peiró, Rosanna

    2008-04-01

    Motor road transport has increased exponentially in the last few years. To a large extent, mobility is an essential element in the organization of society, but, until recently, the implications of chosen forms of transport for health and the environment have not been considered. In this chapter we review the negative impact of current forms of transport on health in terms of traffic injuries, climate change, atmospheric contamination, noise, and interference with daily activities and exercise, such as impediments to walking or cycling. Some possible interventions related to the instruments available in public health and other fields are proposed. Issues deserving further research are highlighted. Some examples in Spain and other countries are described. Recommendations are made on the need to reduce the use of private cars and to develop segmented routes and areas of quiet traffic connected in the cities and among nearby towns to promote walking are cycling. One major goal in current public policies should be to develop and maintain a public transport system that is safe, cheap and faster and less polluting than private transport. These interventions would help to achieve a change in current modes of transport and would lead to a healthier population and a more sustainable environment.

  13. Transport experiments with Dirac electrons

    NASA Astrophysics Data System (ADS)

    Checkelsky, Joseph George

    This thesis presents transport experiments performed on solid state systems in which the behavior of the charge carriers can be described by the Dirac equation. Unlike the massive carriers in a typical material, in these systems the carriers behave like massless fermions with a photon-like dispersion predicted to greatly modify their spin and charge transport properties. The first system studied is graphene, a crystalline monolayer of carbon arranged in a hexagonal lattice. The band structure calculated from the hexagonal lattice has the form of the massless Dirac Hamiltonian. At the charge neutral Dirac point, we find that application of a magnetic field drives a transition to an insulating state. We also study the thermoelectric properties of graphene and find that the states near the Dirac point have a unique response compared to those at higher charge density. The second system is the 3D topological insulator Bi2Se3, where a Dirac-like dispersion for states on the 2D surface of the insulating 3D crystal arises as a result of the topology of the 3D bands and time reversal symmetry. To access the transport properties of the 2D states, we suppress the remnant bulk conduction channel by chemical doping and electrostatic gating. In bulk crystals we find strong quantum corrections to transport at low temperature when the bulk conduction channel is maximally suppressed. In microscopic crystals we are able better to isolate the surface conduction channel properties. We identify in-gap conducting states that have relatively high mobility compared to the bulk and exhibit weak anti-localization, consistent with predictions for protected 2D surface states with strong spin-orbit coupling.

  14. Study of Electron Transport and Amplification in Diamond

    SciTech Connect

    Ben-Zvi, Ilan; Muller, Erik

    2015-01-05

    The development of the Diamond Amplified Photocathode (DAP) has produced significant results under our previous HEP funded efforts both on the fabrication of working devices and the understanding of the underlying physics governing its performance. The results presented here substantiate the use of diamond as both a secondary electron amplifier for high-brightness, high-average-current electron sources and as a photon and particle detector in harsh radiation environments. Very high average current densities (>10A/cm2) have been transported through diamond material. The transport has been measured as a function of incident photon energy and found to be in good agreement with theoretical models. Measurements of the charge transport for photon energies near the carbon K-edge (290 eV for sp3 bonded carbon) have provided insight into carrier loss due to diffusion; modeling of this aspect of charge transport is underway. The response of diamond to nanosecond x-ray pulses has been measured; in this regime the charge transport is as expected. Electron emission from hydrogenated diamond has been measured using both electron and x-ray generated carriers; a gain of 178 has been observed for electron-generated carriers. The energy spectrum of the emitted electrons has been measured, providing insight into the electron affinity and ultimately the thermal emittance. The origin of charge trapping in diamond has been investigated for both bulk and surface trapping

  15. The Electron Transport Chain: An Interactive Simulation

    ERIC Educational Resources Information Center

    Romero, Chris; Choun, James

    2014-01-01

    This activity provides students an interactive demonstration of the electron transport chain and chemiosmosis during aerobic respiration. Students use simple, everyday objects as hydrogen ions and electrons and play the roles of the various proteins embedded in the inner mitochondrial membrane to show how this specific process in cellular…

  16. Feminist Interventions in Electronic Environments.

    ERIC Educational Resources Information Center

    Hocks, Mary E.

    1999-01-01

    Notes that feminist interventions are communicative acts that bring attention to shifting power relations within a specific discursive context. Argues that enacting feminist interventions in online environments changes the online community's identity and narrow sense of audience, and that creating feminist multimedia helps ensure a more human,…

  17. Electron transport through single carbon nanotubes

    SciTech Connect

    Schenkel, Thomas; Chai, G.; Heinrich, H.; Chow, L.; Schenkel, T.

    2007-08-01

    We report on the transport of energetic electrons through single, well aligned multi-wall carbon nanotubes (CNT). Embedding of CNTs in a protective carbon fiber coating enables the application of focused ion beam based sample preparation techniques for the non-destructive isolation and alignment of individual tubes. Aligned tubes with lengths of 0.7 to 3 mu m allow transport of 300 keV electrons in a transmission electron microscope through their hollow cores at zero degree incident angles and for a misalignment of up to 1 degree.

  18. Multidimensional Deterministic Electron Transport Calculations

    DTIC Science & Technology

    1992-05-01

    inlllnlnilinlmmm nMI MII n~lA - Is - -The SMART scattering matrix is not tied to a particular angular flux distribution . -There is considerable numerical...Both expressions are derived by performing an uncollided electron balance over the i’th path length cell. The uncollided flux is then distributed to the...OIS1UTInOIAVALAIT Y STAIEMENT LDIOSTRIUTION CODE Approved for public release; distribution unlimited. 13. A8STRACTO"d noww Fast and accurate techniques for

  19. Electronic Transport in Ultrathin Heterostructures.

    DTIC Science & Technology

    1981-10-01

    rqgion consisting of twelve - 50-A GaAs wells alter- Compounds. St. Lois . 1978. edited by C. M. Wolfe asting with thirteen - I0-A AlAs barriers. The ex...alloy range energy range comparable (and competitive) with III-V al- (x < x, -0.45), an obvious limit to the heterobarrier height loys . or energy-gap...International, Electronics Research Center, Anaheim, CA 92803, U.S.A. (Received 3 November 1980 by J. Tauc ) Data are presented on MO-CVD AlGa I, As

  20. Small Substrate Transport and Mechanism of a Molybdate ATP Binding Cassette Transporter in a Lipid Environment*

    PubMed Central

    Rice, Austin J.; Harrison, Alistair; Alvarez, Frances J. D.; Davidson, Amy L.; Pinkett, Heather W.

    2014-01-01

    Embedded in the plasma membrane of all bacteria, ATP binding cassette (ABC) importers facilitate the uptake of several vital nutrients and cofactors. The ABC transporter, MolBC-A, imports molybdate by passing substrate from the binding protein MolA to a membrane-spanning translocation pathway of MolB. To understand the mechanism of transport in the biological membrane as a whole, the effects of the lipid bilayer on transport needed to be addressed. Continuous wave-electron paramagnetic resonance and in vivo molybdate uptake studies were used to test the impact of the lipid environment on the mechanism and function of MolBC-A. Working with the bacterium Haemophilus influenzae, we found that MolBC-A functions as a low affinity molybdate transporter in its native environment. In periods of high extracellular molybdate concentration, H. influenzae makes use of parallel molybdate transport systems (MolBC-A and ModBC-A) to take up a greater amount of molybdate than a strain with ModBC-A alone. In addition, the movement of the translocation pathway in response to nucleotide binding and hydrolysis in a lipid environment is conserved when compared with in-detergent analysis. However, electron paramagnetic resonance spectroscopy indicates that a lipid environment restricts the flexibility of the MolBC translocation pathway. By combining continuous wave-electron paramagnetic resonance spectroscopy and substrate uptake studies, we reveal details of molybdate transport and the logistics of uptake systems that employ multiple transporters for the same substrate, offering insight into the mechanisms of nutrient uptake in bacteria. PMID:24722984

  1. Radiation Hardened Electronics for Space Environments (RHESE)

    NASA Technical Reports Server (NTRS)

    Keys, Andrew S.; Adams, James H.; Frazier, Donald O.; Patrick, Marshall C.; Watson, Michael D.; Johnson, Michael A.; Cressler, John D.; Kolawa, Elizabeth A.

    2007-01-01

    Radiation Environmental Modeling is crucial to proper predictive modeling and electronic response to the radiation environment. When compared to on-orbit data, CREME96 has been shown to be inaccurate in predicting the radiation environment. The NEDD bases much of its radiation environment data on CREME96 output. Close coordination and partnership with DoD radiation-hardened efforts will result in leveraged - not duplicated or independently developed - technology capabilities of: a) Radiation-hardened, reconfigurable FPGA-based electronics; and b) High Performance Processors (NOT duplication or independent development).

  2. Electron Transport in Solvated Porous Nanocarbons

    NASA Astrophysics Data System (ADS)

    Baskin, Artem; Kral, Petr

    2013-03-01

    We study electron transport in porous nanocarbons (PNCs) in vacuum, gases, and ionic solutions. Using state of the art electronic structure methods and nonequilibrium Green's functions techniques, we explore the band structures and the current-voltage characteristics of PNCs with different sizes, shapes, positioning and functionalization of pores, edges, and types of electrodes. We find that the presence of ions and molecules around PNCs can largely influence their electron transmissivity. Therefore, PNCs could be used for highly sensitive detection of ions and polar molecules passing around them.

  3. Numerical solution of the electron transport equation

    NASA Astrophysics Data System (ADS)

    Woods, Mark

    The electron transport equation has been solved many times for a variety of reasons. The main difficulty in its numerical solution is that it is a very stiff boundary value problem. The most common numerical methods for solving boundary value problems are symmetric collocation methods and shooting methods. Both of these types of methods can only be applied to the electron transport equation if the boundary conditions are altered with unrealistic assumptions because they require too many points to be practical. Further, they result in oscillating and negative solutions, which are physically meaningless for the problem at hand. For these reasons, all numerical methods for this problem to date are a bit unusual because they were designed to try and avoid the problem of extreme stiffness. This dissertation shows that there is no need to introduce spurious boundary conditions or invent other numerical methods for the electron transport equation. Rather, there already exists methods for very stiff boundary value problems within the numerical analysis literature. We demonstrate one such method in which the fast and slow modes of the boundary value problem are essentially decoupled. This allows for an upwind finite difference method to be applied to each mode as is appropriate. This greatly reduces the number of points needed in the mesh, and we demonstrate how this eliminates the need to define new boundary conditions. This method is verified by showing that under certain restrictive assumptions, the electron transport equation has an exact solution that can be written as an integral. We show that the solution from the upwind method agrees with the quadrature evaluation of the exact solution. This serves to verify that the upwind method is properly solving the electron transport equation. Further, it is demonstrated that the output of the upwind method can be used to compute auroral light emissions.

  4. Electronic materials processing and the microgravity environment

    NASA Technical Reports Server (NTRS)

    Witt, A. F.

    1988-01-01

    The nature and origin of deficiencies in bulk electronic materials for device fabrication are analyzed. It is found that gravity generated perturbations during their formation account largely for the introduction of critical chemical and crystalline defects and, moreover, are responsible for the still existing gap between theory and experiment and thus for excessive reliance on proprietary empiricism in processing technology. Exploration of the potential of reduced gravity environment for electronic materials processing is found to be not only desirable but mandatory.

  5. Modeling electronic quantum transport with machine learning

    NASA Astrophysics Data System (ADS)

    Lopez-Bezanilla, Alejandro; von Lilienfeld, O. Anatole

    2014-06-01

    We present a machine learning approach to solve electronic quantum transport equations of one-dimensional nanostructures. The transmission coefficients of disordered systems were computed to provide training and test data sets to the machine. The system's representation encodes energetic as well as geometrical information to characterize similarities between disordered configurations, while the Euclidean norm is used as a measure of similarity. Errors for out-of-sample predictions systematically decrease with training set size, enabling the accurate and fast prediction of new transmission coefficients. The remarkable performance of our model to capture the complexity of interference phenomena lends further support to its viability in dealing with transport problems of undulatory nature.

  6. The effect of electron-electron interaction induced dephasing on electronic transport in graphene nanoribbons

    SciTech Connect

    Kahnoj, Sina Soleimani; Touski, Shoeib Babaee; Pourfath, Mahdi E-mail: pourfath@iue.tuwien.ac.at

    2014-09-08

    The effect of dephasing induced by electron-electron interaction on electronic transport in graphene nanoribbons is theoretically investigated. In the presence of disorder in graphene nanoribbons, wavefunction of electrons can set up standing waves along the channel and the conductance exponentially decreases with the ribbon's length. Employing the non-equilibrium Green's function formalism along with an accurate model for describing the dephasing induced by electron-electron interaction, we show that this kind of interaction prevents localization and transport of electrons remains in the diffusive regime where the conductance is inversely proportional to the ribbon's length.

  7. Public Service Guidelines in an Electronic Environment.

    ERIC Educational Resources Information Center

    Barkley, Daniel C.

    1998-01-01

    In today's electronic environment, government information librarians face new challenges, especially in the arena of quality public-service provision. Given the lack of clear guidelines that Federal Depository Library Program participants follow, and based upon suggested guidelines of reference-oriented literature, a new set of public services…

  8. Censorship, the Classroom, and the Electronic Environment.

    ERIC Educational Resources Information Center

    Considine, David M.

    1985-01-01

    Suggests that the notion that the young can be protected by denying them access to materials has been invalidated by the expansion of the electronic environment and changes in community standards. Argues that since students today cannot avoid exposure to questionable material, it is important to see that the exposure they receive is educated and…

  9. Self-consistent electron transport in tokamaks

    SciTech Connect

    Gatto, R.; Chavdarovski, I.

    2007-09-15

    Electron particle, momentum, and energy fluxes in axisymmetric toroidal devices are derived from a version of the action-angle collision operator that includes both diffusion and drag in action-space [D. A. Hitchcock, R. D. Hazeltine, and S. M. Mahajan, Phys. Fluids 26, 2603 (1983); H. E. Mynick, J. Plasma Phys. 39, 303 (1988)]. A general result of the theory is that any contribution to transport originating directly from the toroidal frequency of the particle motion is constrained to be zero when the electron temperature is equal to the ion temperature. In particular, this constraint applies to those components of the particle and energy fluxes that are proportional to the magnetic shear, independent of the underlying turbulence and of whether the particles are trapped or untrapped. All the total fluxes describing collisionless transport of passing electrons in steady-state magnetic turbulence contain contributions proportional to the conventional thermodynamic drives, which are always outward, and contributions proportional to the magnetic shear, which have both magnitude and sign dependent on the ion-electron temperature ratio. The turbulent generalization of Ohm's law includes a hyper-resistive term, which flattens the current density profile on a fast time scale, and a turbulent electric field, which can have both signs depending on the electron-ion temperature ratio.

  10. Extracellular Electron Transport (EET): Metal Cycling in Extreme Places

    NASA Astrophysics Data System (ADS)

    Nealson, K. H.

    2014-12-01

    Extracellular electron transport, or EET, is the process whereby bacteria either donate electrons to an electron acceptor (usually insoluble), or take up electrons from and electron donor (usually insoluble) that is located outside the cell. Iron cycling is inherently linked to EET, as both reduced iron (electron donors), and oxidized iron (electron acceptors) can be found as insoluble minerals, and require specialized molecular machines to accomplish these extracellular geobiological reactions. Bacteria in the group Shewanella are able to catalyze EET in both directions, and are involved with a number of different iron conversions, but are not good role models for extreme conditions - to our knowledge there are no shewanellae that are tolerant to extremes of temperature or pH, the two usual. This being said, when cells are energy starved via limitation for electron acceptors, they respond by turning on the system(s) for EET. Thus, in this presentation the known mechanism(s) of EET will be discussed, along with recent findings and reports of EET-capable organisms from a variety of extreme environments. From these data, I put forward the hypothesis that there are many microbes (many of them from extreme environments) that will be resistant to cultivation by "standard microbiological methods", yet lend themselves well to cultivation via electrochemical methods.

  11. Electron transport fluxes in potato plateau regime

    SciTech Connect

    Shaing, K.C.; Hazeltine, R.D.

    1997-12-01

    Electron transport fluxes in the potato plateau regime are calculated from the solutions of the drift kinetic equation and fluid equations. It is found that the bootstrap current density remains finite in the region close to the magnetic axis, although it decreases with increasing collision frequency. This finite amount of the bootstrap current in the relatively collisional regime is important in modeling tokamak startup with 100{percent} bootstrap current. {copyright} {ital 1997 American Institute of Physics.}

  12. Electronic transport in arrays of gold nanocrystals

    NASA Astrophysics Data System (ADS)

    Parthasarathy, Raghuveer

    We examine electronic transport through two-dimensional arrays of gold nanocrystals. Recently developed techniques of particle synthesis and array self-assembly provide ordered (and disordered) monolayers of six-nanometer diameter gold nanocrystals on substrates with in-plane electrodes. These well-characterized superlattices allow investigation of basic questions about electronic conduction in metal quantum dot assemblies, answers to which have previously remained elusive. We first address the relation between current and voltage. Central to transport is the Coulomb blockade, the energetic cost of adding a single electron to a nanocrystal. Theoretical studies suggest power-law scaling of current beyond a threshold voltage in Coulomb blockade dominated systems. In ordered arrays, our data follow a power-law form, but with a scaling exponent significantly higher than the theoretical prediction. In disordered arrays, power-law scaling is violated; we explain that disorder disturbs the branching of current-carrying paths responsible for power-law conduction. Second, we examine the effect of temperature on transport. We find a large low-temperature regime (up to about 100 K) in which thermal energy acts only to linearly suppress the threshold voltage, leaving the current scale unaffected. We provide a simple, analytic model of thermally assisted tunneling which quantitatively describes the data. Third, we develop a simple and novel technique to tune the interparticle electronic couplings of the arrays---deposition of small amounts of germanium on the monolayers. The germanium dopant lowers the voltage threshold, and also increases conductivity. It also increases the temperature dependence of transport, suggesting the introduction of trapped states between the gold nanocrystal cores.

  13. Electronic transport in methylated fragments of DNA

    NASA Astrophysics Data System (ADS)

    de Almeida, M. L.; Oliveira, J. I. N.; Lima Neto, J. X.; Gomes, C. E. M.; Fulco, U. L.; Albuquerque, E. L.; Freire, V. N.; Caetano, E. W. S.; de Moura, F. A. B. F.; Lyra, M. L.

    2015-11-01

    We investigate the electronic transport properties of methylated deoxyribonucleic-acid (DNA) strands, a biological system in which methyl groups are added to DNA (a major epigenetic modification in gene expression), sandwiched between two metallic platinum electrodes. Our theoretical simulations apply an effective Hamiltonian based on a tight-binding model to obtain current-voltage curves related to the non-methylated/methylated DNA strands. The results suggest potential applications in the development of novel biosensors for molecular diagnostics.

  14. Electronic transport in methylated fragments of DNA

    SciTech Connect

    Almeida, M. L. de; Oliveira, J. I. N.; Lima Neto, J. X.; Gomes, C. E. M.; Fulco, U. L. Albuquerque, E. L.; Freire, V. N.; Caetano, E. W. S.; Moura, F. A. B. F. de; Lyra, M. L.

    2015-11-16

    We investigate the electronic transport properties of methylated deoxyribonucleic-acid (DNA) strands, a biological system in which methyl groups are added to DNA (a major epigenetic modification in gene expression), sandwiched between two metallic platinum electrodes. Our theoretical simulations apply an effective Hamiltonian based on a tight-binding model to obtain current-voltage curves related to the non-methylated/methylated DNA strands. The results suggest potential applications in the development of novel biosensors for molecular diagnostics.

  15. Electronic transport in smectic liquid crystals

    NASA Astrophysics Data System (ADS)

    Shiyanovskaya, I.; Singer, K. D.; Twieg, R. J.; Sukhomlinova, L.; Gettwert, V.

    2002-04-01

    Time-of-flight measurements of transient photoconductivity have revealed bipolar electronic transport in phenylnaphthalene and biphenyl liquid crystals (LC), which exhibit several smectic mesophases. In the phenylnaphthalene LC, the hole mobility is significantly higher than the electron mobility and exhibits different temperature and phase behavior. Electron mobility in the range ~10-5 cm2/V s is temperature activated and remains continuous at the phase transitions. However, hole mobility is nearly temperature independent within the smectic phases, but is very sensitive to smectic order, 10-3 cm2/V s in the smectic-B (Sm-B) and 10-4 cm2/V s in the smectic-A (Sm-A) mesophases. The different behavior for holes and electron transport is due to differing transport mechanisms. The electron mobility is apparently controlled by rate-limiting multiple shallow trapping by impurities, but hole mobility is not. To explain the lack of temperature dependence for hole mobility within the smectic phases we consider two possible polaron transport mechanisms. The first mechanism is based on the hopping of Holstein small polarons in the nonadiabatic limit. The polaron binding energy and transfer integral values, obtained from the model fit, turned out to be sensitive to the molecular order in smectic mesophases. A second possible scenario for temperature-independent hole mobility involves the competion between two different polaron mechanisms involving so-called nearly small molecular polarons and small lattice polarons. Although the extracted transfer integrals and binding energies are reasonable and consistent with the model assumptions, the limited temperature range of the various phases makes it difficult to distinguish between any of the models. In the biphenyl LCs both electron and hole mobilities exhibit temperature activated behavior in the range of 10-5 cm2/V s without sensitivity to the molecular order. The dominating transport mechanism is considered as multiple trapping

  16. Runaway electron transport via tokamak microturbulence

    SciTech Connect

    Hauff, T.; Jenko, F.

    2009-10-15

    The mechanisms found for the magnetic transport of fast ions in the work of Hauff et al. [Phys. Rev. Lett. 102, 075004 (2009)] are extended to the diffusion of runaway electrons. Due to their smaller mass and larger energy, they behave strongly relativistically, for which reason the scaling laws defined previously have to be modified. It is found that due to these changes, the regime of constant magnetic transport does not exist anymore, but diffusivity scales with E{sup -1} for magnetic transport, or even with E{sup -2} in the case that finite gyroradius effects become important. It is shown that the modified analytical approaches are able to explain the surprisingly small values found in experiments, although it cannot be excluded that possibly other reduction mechanisms are present at the same time.

  17. Electronic transport properties in graphene oxide frameworks

    NASA Astrophysics Data System (ADS)

    Zhu, P.; Cruz-Silva, E.; Meunier, V.

    2014-02-01

    The electronic transport properties in multiterminal graphene oxide framework (GOF) materials are investigated using a combination of theoretical and computational methods. GOFs make up four-terminal [origin=c]90H-shaped GNR-L-GNR junctions where sandwiched boronic acid molecules (L) are covalently linked to two graphene nanoribbons (GNRs) of different edge chiralities. The transport properties are governed by both tunneling and quasiresonant regimes. We determine how the presence of linker molecules affects the transport properties and establish that the through-molecule transport properties can be tuned by varying the chemical composition of the pillar molecules but are not significantly modified when changing the type of electrodes from zigzag GNRs to armchair GNRs. In addition, we find that in multilinker systems containing two parallel molecules in the device area, the coupling between the molecules can lead to both constructive and destructive quantum interferences. We also examine the inability of the classical Kirchhoff's superposition law to account for electron flow in multilinker GOF nanonetworks.

  18. Quantum electron transport in toroidal carbon nanotubes

    NASA Astrophysics Data System (ADS)

    Jack, Mark; Encinosa, Mario

    2008-03-01

    Electron transport under bias is treated in tight-binding approximation using a non-equilibrium Green's function approach. Density-of-states D(E), transmissivity T(E), and current ISD are calculated through a (3,3) armchair nanotorus with laterally attached metallic leads and a magnetic field penetrating the toroidal plane. Plateaus in T(E) through the torus are observed as a function of both the relative angle between leads and magnetic flux. Initial computational studies performed with 1800 atoms and attached leads show substantial computational slowdown when increasing the system size by a factor of two. Results are generated by inverting the device Hamiltonian with a standard recursion method extended to account for unit cell toroidal closure. Significant computational speed-up is expected for a parallelized code on a multiprocessor computer cluster. The dependence of electronic features on torus size and torus curvature is tested for three tori with 900, 1800 and 3600 carbon atoms, respectively. References: 1. M. Jack and M. Encinosa, Quantum electron transport in toroidal carbon nanotubes with metallic leads. ArXiv: quant-ph/0709.0760. 2. M. Encinosa and M. Jack, Dipole and solenoidal magnetic moments of electronic surface currents on toroidal nanostructures. J. Comp.-Aided Mat. Design (Springer), 14 (1) (2007) 65 -- 71.

  19. Studies of runaway electron transport in TEXT

    SciTech Connect

    Wang, Pei-Wen.

    1991-12-01

    The transport of runaway electrons is studied by a plasma position shift experiment and by imposing an externally applied perturbing magnetic field on the edge. The perturbing magnetic field can produce either magnetic islands or, with overlapping islands, a stochastic field. Hard X-ray signals are then measured and compared with analytic and numerical model results. Diffusion coefficients in the edge, {approximately}10{sup 4} cm{sup 2}/sec, and inside the plasma, {approximately}10{sup 2} {minus} 10{sup 3} cm{sup 2}/sec, are estimated. The averaged drift effects are small and the intrinsic magnetic fluctuations are estimated to be < (b{sub r}/B{sub 0}){sup 2} > {approximately}1-{sup {minus}10} at the edge and decreasing inward. Runaway electrons are a good diagnostic of the magnetic fluctuations. It is considered that the magnetic fluctuations have a negligible effect on electron thermal diffusion in the edge plasma.

  20. On electron transport through Geobacter biofilms.

    PubMed

    Bond, Daniel R; Strycharz-Glaven, Sarah M; Tender, Leonard M; Torres, César I

    2012-06-01

    Geobacter spp. can form a biofilm that is more than 20 μm thick on an anode surface by utilizing the anode as a terminal respiratory electron acceptor. Just how microbes transport electrons through a thick biofilm and across the biofilm/anode interface, and what determines the upper limit to biofilm thickness and catalytic activity (i.e., current, the rate at which electrons are transferred to the anode), are fundamental questions attracting substantial attention. A significant body of experimental evidence suggests that electrons are transferred from individual cells through a network of cytochromes associated with cell outer membranes, within extracellular polymeric substances, and along pili. Here, we describe what is known about this extracellular electron transfer process, referred to as electron superexchange, and its proposed role in biofilm anode respiration. Superexchange is able to account for many different types of experimental results, as well as for the upper limit to biofilm thickness and catalytic activity that Geobacter biofilm anodes can achieve.

  1. Electronic transport in graphene-based heterostructures

    SciTech Connect

    Tan, J. Y.; Avsar, A.; Balakrishnan, J.; Taychatanapat, T.; O'Farrell, E. C. T.; Eda, G.; Castro Neto, A. H.; Koon, G. K. W.; Özyilmaz, B.; Watanabe, K.; Taniguchi, T.

    2014-05-05

    While boron nitride (BN) substrates have been utilized to achieve high electronic mobilities in graphene field effect transistors, it is unclear how other layered two dimensional (2D) crystals influence the electronic performance of graphene. In this Letter, we study the surface morphology of 2D BN, gallium selenide (GaSe), and transition metal dichalcogenides (tungsten disulfide (WS{sub 2}) and molybdenum disulfide (MoS{sub 2})) crystals and their influence on graphene's electronic quality. Atomic force microscopy analysis shows that these crystals have improved surface roughness (root mean square value of only ∼0.1 nm) compared to conventional SiO{sub 2} substrate. While our results confirm that graphene devices exhibit very high electronic mobility (μ) on BN substrates, graphene devices on WS{sub 2} substrates (G/WS{sub 2}) are equally promising for high quality electronic transport (μ ∼ 38 000 cm{sup 2}/V s at room temperature), followed by G/MoS{sub 2} (μ ∼ 10 000 cm{sup 2}/V s) and G/GaSe (μ ∼ 2200 cm{sup 2}/V s). However, we observe a significant asymmetry in electron and hole conduction in G/WS{sub 2} and G/MoS{sub 2} heterostructures, most likely due to the presence of sulphur vacancies in the substrate crystals. GaSe crystals are observed to degrade over time even under ambient conditions, leading to a large hysteresis in graphene transport making it a less suitable substrate.

  2. Hetero-Interfaces for Extreme Electronic Environments

    DTIC Science & Technology

    2014-07-23

    ELECTRONIC ENVIRONMENTS Quasi-two-dimensional electron gas (Q-2D-EG) forms at the interface between two perovskite band insulators; LaAlO3 (LAO) and...BO2 stacking in perovskite phase (Fig. 1) [2]. For example, a SrTiO3/LaAlO3 interface normal to > produces a charge- balanced layer of SrTiO3...pointing out that interfacial strain in a perovskite heterostructure has been shown to alter its physical properties. For example, thin film STO can exhibit

  3. Hetero-Interfaces For Extreme Electronic Environments

    DTIC Science & Technology

    2014-07-23

    between two perovskite insulators (i.e., LaAlO3 on SrTiO3) was first reported in 2004.[1] This unexpected result was related to internal polarization...INTERFACES FOR EXTREME ELECTRONIC ENVIRONMENTS Quasi-two-dimensional electron gas (Q-2D-EG) forms at the interface between two perovskite band...orientation provides AO – BO2 stacking in perovskite phase (Fig. 1) [2]. For example, a SrTiO3/LaAlO3 interface normal to > produces a charge

  4. Logistics, electronic commerce, and the environment

    NASA Astrophysics Data System (ADS)

    Sarkis, Joseph; Meade, Laura; Talluri, Srinivas

    2002-02-01

    Organizations realize that a strong supporting logistics or electronic logistics (e-logistics) function is important from both commercial and consumer perspectives. The implications of e-logistics models and practices cover the forward and reverse logistics functions of organizations. They also have direct and profound impact on the natural environment. This paper will focus on a discussion of forward and reverse e-logistics and their relationship to the natural environment. After discussion of the many pertinent issues in these areas, directions of practice and implications for study and research are then described.

  5. The AE-8 trapped electron model environment

    NASA Technical Reports Server (NTRS)

    Vette, James I.

    1991-01-01

    The machine sensible version of the AE-8 electron model environment was completed in December 1983. It has been sent to users on the model environment distribution list and is made available to new users by the National Space Science Data Center (NSSDC). AE-8 is the last in a series of terrestrial trapped radiation models that includes eight proton and eight electron versions. With the exception of AE-8, all these models were documented in formal reports as well as being available in a machine sensible form. The purpose of this report is to complete the documentation, finally, for AE-8 so that users can understand its construction and see the comparison of the model with the new data used, as well as with the AE-4 model.

  6. Distribution of tunnelling times for quantum electron transport

    NASA Astrophysics Data System (ADS)

    Rudge, Samuel L.; Kosov, Daniel S.

    2016-03-01

    In electron transport, the tunnelling time is the time taken for an electron to tunnel out of a system after it has tunnelled in. We define the tunnelling time distribution for quantum processes in a dissipative environment and develop a practical approach for calculating it, where the environment is described by the general Markovian master equation. We illustrate the theory by using the rate equation to compute the tunnelling time distribution for electron transport through a molecular junction. The tunnelling time distribution is exponential, which indicates that Markovian quantum tunnelling is a Poissonian statistical process. The tunnelling time distribution is used not only to study the quantum statistics of tunnelling along the average electric current but also to analyse extreme quantum events where an electron jumps against the applied voltage bias. The average tunnelling time shows distinctly different temperature dependence for p- and n-type molecular junctions and therefore provides a sensitive tool to probe the alignment of molecular orbitals relative to the electrode Fermi energy.

  7. Unconventional dc Transport in Rashba Electron Gases.

    PubMed

    Brosco, Valentina; Benfatto, Lara; Cappelluti, Emmanuele; Grimaldi, Claudio

    2016-04-22

    We discuss the transport properties of a disordered two-dimensional electron gas with strong Rashba spin-orbit coupling. We show that in the high-density regime where the Fermi energy overcomes the energy associated with spin-orbit coupling, dc transport is accurately described by a standard Drude's law, due to a nontrivial compensation between the suppression of backscattering and the relativistic correction to the quasiparticle velocity. On the contrary, when the system enters the opposite dominant spin-orbit regime, Drude's paradigm breaks down and the dc conductivity becomes strongly sensitive to the spin-orbit coupling strength, providing a suitable tool to test the entanglement between spin and charge degrees of freedom in these systems.

  8. An environment-dependent semi-empirical tight binding model suitable for electron transport in bulk metals, metal alloys, metallic interfaces, and metallic nanostructures. II. Application—Effect of quantum confinement and homogeneous strain on Cu conductance

    SciTech Connect

    Hegde, Ganesh Povolotskyi, Michael; Kubis, Tillmann; Charles, James; Klimeck, Gerhard

    2014-03-28

    The Semi-Empirical tight binding model developed in Part I Hegde et al. [J. Appl. Phys. 115, 123703 (2014)] is applied to metal transport problems of current relevance in Part II. A systematic study of the effect of quantum confinement, transport orientation, and homogeneous strain on electronic transport properties of Cu is carried out. It is found that quantum confinement from bulk to nanowire boundary conditions leads to significant anisotropy in conductance of Cu along different transport orientations. Compressive homogeneous strain is found to reduce resistivity by increasing the density of conducting modes in Cu. The [110] transport orientation in Cu nanowires is found to be the most favorable for mitigating conductivity degradation since it shows least reduction in conductance with confinement and responds most favorably to compressive strain.

  9. Electronic transport in Pd nanocluster devices

    NASA Astrophysics Data System (ADS)

    Ayesh, A. I.

    2011-03-01

    Palladium nanoclusters with an average diameter of 6.7 nm are prepared by magnetron sputtering and inert gas condensation technique. The nanoclusters are deposited between a pair of electrodes defined by optical lithography to create the device. The electronic transport in the devices is investigated by systematic current-voltage measurements. It is demonstrated through fitting the conductance-temperature profile into a conductance model that the conductance in the device is dominated by tunneling. The fitting provides meaningful physical parameters such as the number of nanoclusters within the conduction path, and it shows that some of the nanoclusters are fused together.

  10. Electronic and Ionic Transport in Polymers.

    DTIC Science & Technology

    1988-04-06

    PROCUREMENT INSTRUMENT IDENTIFICATION NUMBER ORGANIZATION Defense Advanced (if applicable) Research Projects Agency DARPA 1100014-86-K-0769 8c ADDRESS...include Area Code) I22c. OFFiC_: SYM80L Dr. JoAnn Millikan (202) 696-4410 1 DO FORM 1473,84 -MAR 83 APR eaition may be usea until exnaustea. SECURITY...3811 Cognizant ONR Scientific Officer: Dr. JoAnn Millikan Contract No.: N00014-86-K-0769 Short Title of Work: "Electronic and Ionic Transport in Polymers

  11. RHIC electron lens beam transport system design considerations

    SciTech Connect

    Luo, Y.; Heimerle, M.; Fischer, W.; Pikin, A.; Beebe, E.; Bruno, D.; Gassner, D.; Gu, X.; Gupta, R. C.; Hock, J.; Jain, A.; Lambiase, R.; Mapes, M.; Meng, W.; Montag, C.; Oerter, B.; Okamura, M.; Raparia, D.; Tan, Y.; Than, R.; Tuozzolo, J.; Zhang, W.

    2010-08-03

    To apply head-on beam-beam compensation for RHIC, two electron lenses are designed and will be installed at IP6 and IP8. Each electron lens has several sub-systems, including electron gun, electron collector, superconducting main solenoid (SM), diagnostics system and power supply system. In addition to these systems, beam transport system which can transport electron beam from electron gun side to collector side is also needed.

  12. Electron Transport through Porphyrin Molecular Junctions

    NASA Astrophysics Data System (ADS)

    Zhou, Qi

    The goal of this work is to study the properties that would affect the electron transport through a porphyrin molecular junction. This work contributes to the field of electron transport in molecular junctions in the following 3 aspects. First of all, by carrying out experiments comparing the conductance of the iron (III) porphyrin (protected) and the free base porphyrin (protected), it is confirmed that the molecular energy level broadening and shifting occurs for porphyrin molecules when coupled with the metal electrodes, and this level broadening and shifting plays an important role in the electron transport through molecular junctions. Secondly, by carrying out an in-situ deprotection of the acetyl-protected free base porphyrin molecules, it is found out that the presence of acetyl groups reduces the conductance. Thirdly, by incorporating the Matrix-assisted laser desorption/ionization (MALDI) spectrum and the in-situ deprotection prior to formation of molecular junctions, it allows a more precise understanding of the molecules involved in the formation of molecular junctions, and therefore allows an accurate analysis of the conductance histogram. The molecules are prepared by self-assembly and the junctions are formed using a Scanning Tunneling Microscopy (STM) molecular break junction technique. The porphyrin molecules are characterized by MALDI in solution before self-assembly to a gold/mica substrate. The self-assembled monolayers (SAMs) of porphyrins on gold are characterized by Ultraviolet-visible (UV-Vis) reflection spectroscopy to confirm that the molecules are attached to the substrate. The SAMs are then characterized by Angle-Resolved X-ray photoelectron spectroscopy (ARXPS) to determine the thickness and the average molecular orientation of the molecular layer. The electron transport is measured by conductance-displacement (G-S) experiments under a given bias (-0.4V). The conductance value of a single molecule is identified by a statistical analysis

  13. Isolation systems for electronic black-box transportation to orbit

    NASA Astrophysics Data System (ADS)

    Jedrich, Nicholas M.; Pendleton, Scott C.

    1998-06-01

    Servicing the Hubble Space Telescope (HST) requires the safe transportation of electronic Orbital Replacement Units (ORUs) on the Space Transportation System (STS) to replace or enhance the capability of existing units. The delicate design of these electronic ORUs makes it imperative to provide isolation from the STS launch random vibration, while maintaining fundamental modes above the transient load environment. Two methods were developed and used exclusively, on Servicing Mission 2 (SM2), to isolate the ORUs from the environmental launch loads imposed by the STS. The first load isolation system utilizes a refined open/closed cell foam design to provide the required damping and corner frequency, while the second method uses an innovative Viscoelastic Material (VEM) design. This paper addresses both systems as initially designed including finite element (FE) model analysis of the VEM system. Vibration testing of prototype systems and modifications to the design resulting from test will be discussed. The final design as flown on HST SM2 with recommendations for future applications of these technologies in transporting electronic black boxes to orbit will conclude the paper.

  14. Magnetospheric models for electron acceleration and transport in the heliosphere

    NASA Technical Reports Server (NTRS)

    Cooper, J. F.; Baker, D. N.

    1993-01-01

    Electron transport and acceleration processes in the earth's magnetosphere have correspondences to analogous processes affecting electrons in the solar magnetosphere (i.e., heliosphere). Energetic electrons in planetary magnetospheres and the heliosphere are test particles probing transport and acceleration dynamics with minimal effects on dominant magnetic field configurations. Parallels are discussed relating to electron entry into the magnetospheres from interplanetary and interstellar space, circulatory transport processes, and acceleration by electric fields in boundary regions including shocks and magnetotails.

  15. Electronic Cigarette Topography in the Natural Environment.

    PubMed

    Robinson, R J; Hensel, E C; Morabito, P N; Roundtree, K A

    2015-01-01

    This paper presents the results of a clinical, observational, descriptive study to quantify the use patterns of electronic cigarette users in their natural environment. Previously published work regarding puff topography has been widely indirect in nature, and qualitative rather than quantitative, with the exception of three studies conducted in a laboratory environment for limited amounts of time. The current study quantifies the variation in puffing behaviors among users as well as the variation for a given user throughout the course of a day. Puff topography characteristics computed for each puffing session by each subject include the number of subject puffs per puffing session, the mean puff duration per session, the mean puff flow rate per session, the mean puff volume per session, and the cumulative puff volume per session. The same puff topography characteristics are computed across all puffing sessions by each single subject and across all subjects in the study cohort. Results indicate significant inter-subject variability with regard to puffing topography, suggesting that a range of representative puffing topography patterns should be used to drive machine-puffed electronic cigarette aerosol evaluation systems.

  16. Ion age transport: developing devices beyond electronics

    NASA Astrophysics Data System (ADS)

    Demming, Anna

    2014-03-01

    There is more to current devices than conventional electronics. Increasingly research into the controlled movement of ions and molecules is enabling a range of new technologies. For example, as Weihua Guan, Sylvia Xin Li and Mark Reed at Yale University explain, 'It offers a unique opportunity to integrate wet ionics with dry electronics seamlessly'. In this issue they provide an overview of voltage-gated ion and molecule transport in engineered nanochannels. They cover the theory governing these systems and fabrication techniques, as well as applications, including biological and chemical analysis, and energy conversion [1]. Studying the movement of particles in nanochannels is not new. The transport of materials in rock pores led Klinkenberg to describe an analogy between diffusion and electrical conductivity in porous rocks back in 1951 [2]. And already in 1940, Harold Abramson and Manuel Gorin noted that 'When an electric current is applied across the living human skin, the skin may be considered to act like a system of pores through which transfer of substances like ragweed pollen extract may be achieved both by electrophoretic and by diffusion phenomena' [3]. Transport in living systems through pore structures on a much smaller scale has attracted a great deal of research in recent years as well. The selective transport of ions and small organic molecules across the cell membrane facilitates a number of functions including communication between cells, nerve conduction and signal transmission. Understanding these processes may benefit a wide range of potential applications such as selective separation, biochemical sensing, and controlled release and drug delivery processes. In Germany researchers have successfully demonstrated controlled ionic transport through nanopores functionalized with amine-terminated polymer brushes [4]. The polymer nanobrushes swell and shrink in response to changes in temperature, thus opening and closing the nanopore passage to ionic

  17. Electron transport through magnetic quantum point contacts

    NASA Astrophysics Data System (ADS)

    Day, Timothy Ellis

    Spin-based electronics, or spintronics, has generated a great deal of interest as a possible next-generation integrated circuit technology. Recent experimental and theoretical work has shown that these devices could exhibit increased processing speed, decreased power consumption, and increased integration densities as compared with conventional semiconductor devices. The spintronic device that was designed, fabricated, and tested throughout the course of this work aimed to study the generation of spin-polarized currents in semiconductors using magnetic fringe fields. The device scheme relied on the Zeeman effect in combination with a quantum mechanical barrier to generate spin-polarized currents. The Zeeman effect was used to break the degeneracy of spin-up and spin-down electrons and the quantum mechanical potential to transmit one while rejecting the other. The design was dictated by the drive to maximize the strength of the magnetic fringe field and in turn maximize the energy separation of the two spin species. The device was fabricated using advanced techniques in semiconductor processing including electron beam lithography and DC magnetron sputtering. Measurements were performed in a 3He cryostat equipped with a superconducting magnet at temperatures below 300 mK. Preliminary characterization of the device revealed magnetoconductance oscillations produced by the effect of the transverse confining potential on the density of states and the mobility. Evidence of the effect of the magnetic fringe fields on the transport properties of electrons in the device were observed in multiple device measurements. An abrupt washout of the quantized conductance steps was observed over a minute range of the applied magnetic field. The washout was again observed as electrons were shifted closer to the magnetic gates. In addition, bias spectroscopy demonstrated that the washout occurred despite stronger electron confinement, as compared to a non-magnetic split-gate. Thus, the

  18. Transportation and the Environment. Publication No. 74-2.

    ERIC Educational Resources Information Center

    Fagan, James S.

    The increasingly important role of transportation and its environmental impact is given major emphasis in this curriculum unit for secondary students. Four purposes of this unit are to describe and show (1) the historical development of transportation in America; (2) the effect of current transportation practices upon the environment; (3) some…

  19. Discovering Narrative Transportation in an Education Environment

    ERIC Educational Resources Information Center

    Miner, Eric F.

    2014-01-01

    Narrative transportation occurs when people become emotionally immersed in stories, such that they feel imaginatively conveyed into story worlds. This study investigated the lived experiences of students who encountered narrative transportation in a college classroom. It is of interest to psychologists and educational practitioners because…

  20. Effects of Cu deficiency on photosynthetic electron transport

    SciTech Connect

    Droppa, M.; Terry, N.; Horvath, G.

    1984-04-01

    The role of copper (Cu) in photosynthetic electron transport was explored by using Cu deficiency in sugar beet as an experimental approach. Copper influenced electron transport at two sites in addition to plastocyanin. Under mild deficiency (0.84 nmol of Cu per cm/sup 2/ of leaf area), electron transport between the two photosystems (PS) is inhibited but not electron transport within PS I or PS II measured separately. The chlorophyll/plastoquinone ratio was normal in Cu-deficient plants. However, the breakpoint in the Arrhenius plot of electron transport was shifted towards a higher temperature. It is concluded that Cu is necessary to maintain the appropriate membrane fluidity to ensure the mobility of plastoquinone molecules to transfer electrons between the two photosystems. Under severe deficiency (0.22 nmol of Cu per cm/sup 2/ of leaf area) both PS II and PS I electron transports were inhibited and to the same extent. PS II electron transport activity could not be restored by adding artifical electron donors. Polypeptides with M/sub r/s of 28,000 and 13,500 were missing in Cu-deficient chloroplast membranes. In PS II particles prepared from normal chloroplasts of spinach, 2 atoms of Cu per reaction center are present. We conclude that Cu influences PS II electron transport either directly, by participation in electron transfer as a constituent of an electron carrier, or indirectly, via the polypeptide composition of the membrane in the PS II complex.

  1. Electron scattering and transport in liquid argon

    SciTech Connect

    Boyle, G. J.; Cocks, D. G.; White, R. D.; McEachran, R. P.

    2015-04-21

    The transport of excess electrons in liquid argon driven out of equilibrium by an applied electric field is revisited using a multi-term solution of Boltzmann’s equation together with ab initio liquid phase cross-sections calculated using the Dirac-Fock scattering equations. The calculation of liquid phase cross-sections extends previous treatments to consider multipole polarisabilities and a non-local treatment of exchange, while the accuracy of the electron-argon potential is validated through comparison of the calculated gas phase cross-sections with experiment. The results presented highlight the inadequacy of local treatments of exchange that are commonly used in liquid and cluster phase cross-section calculations. The multi-term Boltzmann equation framework accounting for coherent scattering enables the inclusion of the full anisotropy in the differential cross-section arising from the interaction and the structure factor, without an a priori assumption of quasi-isotropy in the velocity distribution function. The model, which contains no free parameters and accounts for both coherent scattering and liquid phase screening effects, was found to reproduce well the experimental drift velocities and characteristic energies.

  2. Electronic Transport in Novel Graphene Nanostructures

    NASA Astrophysics Data System (ADS)

    Gannett, William Joy

    Graphene, a single sheet of sp2-bonded carbon atoms, is a two-dimensional material with an array of unique electronic, chemical, and mechanical properties. Applications including high performance transistors, chemical sensors, and composite materials have already been demonstrated. The introduction of chemical vapor deposition growth of monolayer graphene was an important step towards scalability of such devices. In addition to scalability, the exploration and application of these properties require the fabrication of high quality devices with low carrier scattering. They also require the development of unique geometries and materials combinations to exploit the highly tunable nature of graphene. This dissertation presents the synthesis of materials, fabrication of devices, and measurement of those devices for three previously unexplored types of graphene devices. The first type of device is a field effect transistor made from chemical vapor deposited (CVD) graphene on hexagonal boron nitride (hBN) substrates. We demonstrate a significant improvement in carrier mobility from hBN substrates and are able to explore the sources of scattering in CVD graphene. The second type of device, fluorinated graphene transistors, allows us to examine doping and disorder effects from fluorination of the graphene crystal as well as electronic transport through unfluorinated folds in the graphene. With the third type of device we demonstrate a new route to graphene nanoribbon devices using both hBN flakes and BN nanotubes that may reduce disorder and allow precise measurements of quantum phenomena in graphene nanoribbons.

  3. Transportation: Environment, energy and the economy

    SciTech Connect

    Petrakis, L.

    1993-01-11

    In the US, the transportation sector consumes over one quarter of the entire energy used, almost in its entirety as petroleum products, and in quantities greater than the total US domestic oil production. The transportation sector is responsible for a significant fraction of all emissions that either prevent US cities from achieving compliance with EPA air quality standards or have serious global change implications. Finally, the GDP (Gross Domestic Product) and employment due to the sector are low and incommensurate with the high fraction of energy that the transportation sector consumes. We examine below this situation in some detail and make recommendations for improvements.

  4. Effect of Noise on DNA Sequencing via Transverse Electronic Transport

    PubMed Central

    Krems, Matt; Zwolak, Michael; Pershin, Yuriy V.; Di Ventra, Massimiliano

    2009-01-01

    Abstract Previous theoretical studies have shown that measuring the transverse current across DNA strands while they translocate through a nanopore or channel may provide a statistically distinguishable signature of the DNA bases, and may thus allow for rapid DNA sequencing. However, fluctuations of the environment, such as ionic and DNA motion, introduce important scattering processes that may affect the viability of this approach to sequencing. To understand this issue, we have analyzed a simple model that captures the role of this complex environment in electronic dephasing and its ability to remove charge carriers from current-carrying states. We find that these effects do not strongly influence the current distributions due to the off-resonant nature of tunneling through the nucleotides—a result we expect to be a common feature of transport in molecular junctions. In particular, only large scattering strengths, as compared to the energetic gap between the molecular states and the Fermi level, significantly alter the form of the current distributions. Since this gap itself is quite large, the current distributions remain protected from this type of noise, further supporting the possibility of using transverse electronic transport measurements for DNA sequencing. PMID:19804730

  5. Interstate waste transport -- Emotions, energy, and environment

    SciTech Connect

    Elcock, D.

    1993-12-31

    This report applies quantitative analysis to the debate of waste transport and disposal. Moving from emotions and politics back to numbers, this report estimates potential energy, employment and environmental impacts associated with disposing a ton of municipal solid waste under three different disposal scenarios that reflect interstate and intrastate options. The results help provide a less emotional, more quantitative look at interstate waste transport restrictions.

  6. Interstate waste transport -- Emotions, energy, and environment

    SciTech Connect

    Elcock, D.

    1993-01-01

    This report applies quantitative analysis to the debate of waste transport and disposal. Moving from emotions and politics back to numbers, this report estimates potential energy, employment and environmental impacts associated with disposing a ton of municipal solid waste under three different disposal scenarios that reflect interstate and intrastate options. The results help provide a less emotional, more quantitative look at interstate waste transport restrictions.

  7. Molecular orbital theory of ballistic electron transport through molecules

    NASA Astrophysics Data System (ADS)

    Ernzerhof, Matthias; Rocheleau, Philippe; Goyer, Francois

    2009-03-01

    Electron transport through molecules occurs, for instance, in STM imaging and in conductance measurements on molecular electronic devices (MEDs). To model these phenomena, we use a non-Hermitian model Hamiltonian [1] for the description of open systems that exchange current density with their environment. We derive qualitative, molecular-orbital-based rules relating molecular structure and conductance. We show how side groups attached to molecular conductors [2] can completely suppress the conductance. We discuss interference effects in aromatic molecules [3] that can also inhibit electron transport. Rules are developed [1] for the prediction of Fano resonances. All these phenomena are explained with a molecular orbital theory [1,4] for molecules attached to macroscopic reservoirs. [1] F. Goyer, M. Ernzerhof, and M. Zhuang, JCP 126, 144104 (2007); M. Ernzerhof, JCP 127, 204709 (2007). [2] M. Ernzerhof, M. Zhuang, and P. Rocheleau, JCP 123, 134704 (2005); G. C. Solomon, D Q. Andrews, R P. Van Duyne, and M A. Ratner, JACS 130, 7788 (2008). [3] M. Ernzerhof, H. Bahmann, F. Goyer, M. Zhuang, and P. Rocheleau, JCTC 2, 1291 (2006); G. C. Solomon, D. Q. Andrews, R. P. Van Duyne, and M. A. Ratner, JCP 129, 054701 (2008). [4] B.T. Pickup, P.W. Fowler, CPL 459, 198 (2008); P. Rocheleau and M. Ernzerhof, JCP, submitted.

  8. Electron transport chain defects in heart failure.

    PubMed

    Casademont, Jordi; Miró, Oscar

    2002-04-01

    In recent years, the possibility that disorders of cardiac metabolism play a role in the mechanisms that lead to ventricular dilatation and dysfunction in heart failure has attracted much attention. Electron transport chain is constituted by a series of multimeric protein complexes, located in the inner mitochondrial membranes, whose genes are distributed over both nuclear and mitochondrial DNA. Its normal function is essential to provide the energy for cardiac function. Many studies have described abnormalities in mitochondrial DNA genes encoding for electron transport chain (ETC) in dilated cardiomyopathies. In some cases, heart failure is one more or less relevant symptom among other multisystem manifestations characteristic of mitochondrial encephalomyopathies, being heart failure imputable to a primary mitochondrial disease. In the case of idiopathic dilated cardiomyopathies (IDC), many mitochondrial abnormalities have also been described using hystological, biochemical or molecular studies. The importance of such findings is under debate. The great variability in the mitochondrial abnormalities described has prompted the proposal that mitochondrial dysfunction could be a secondary phenomenon in IDC, and not a primary one. Among other possible explanations for such findings, the presence of an increased oxidative damage due to a free radical excess has been postulated. In this setting, the dysfunction of ETC could be a consequence, but also a cause of the presence of an increased free radical damage. Independently of its origin, ETC dysfunction may contribute to the persistence and worsening of heart failure. If this hypothesis, still to be proven, was certain, the modulation of cardiac metabolism could be an interesting approach to treat IDC. The precise mechanisms that lead to ventricular dilatation and dysfunction in heart failure are still nowadays poorly understood. Circumstances such as cytotoxic insults, viral infections, immune abnormalities

  9. Fate and transport of engineered nanomaterials in the environment.

    PubMed

    Lin, Daohui; Tian, Xiaoli; Wu, Fengchang; Xing, Baoshan

    2010-01-01

    With the fast development of nanotechnology, engineered nanomaterials (ENMs) will inevitably be introduced into the various environment. Increasing studies showed the toxiccity of various ENMs, which raises concerns over their fate and transport in the environment. This review focuses on advances in the research on environmental transport and fate of ENMs. Aggregation and suspension behaviors of ENMs determining their fate and transport in aqueous environment are discussed, with emphasis on the influencing factors, including natural colloids, natural organic matter, pH, and ionic strength. Studies on the transport of ENMs in porous media and its influencing factors are reviewed, and transformation and organismcleansing, as two fate routes of ENMs in the environment, are addressed. Future research directions and outlook in the environmental transport and fate of ENMs are also presented.

  10. Designing a beam transport system for RHIC's electron lens

    SciTech Connect

    Gu, X.; Pikin, A.; Okamura, M.; Fischer, W.; Luo, Y.; Gupta, R.; Hock, J.; Raparia, D.

    2011-03-28

    We designed two electron lenses to apply head-on beam-beam compensation for RHIC; they will be installed near IP10. The electron-beam transport system is an important subsystem of the entire electron-lens system. Electrons are transported from the electron gun to the main solenoid and further to the collector. The system must allow for changes of the electron beam size inside the superconducting magnet, and for changes of the electron position by 5 mm in the horizontal- and vertical-planes.

  11. Charge Transport Characterization of Novel Electronic Materials.

    NASA Astrophysics Data System (ADS)

    Marcy, Henry Orlando, 5th.

    1990-01-01

    The work presented includes analysis of electronic transport data and related measurements for the following types of materials: molecular metals and conducting polymers based upon phthalocyanine (Pc) building blocks, new composites of conducting polymers with inorganic polymeric and layered materials, and both bulk and thin film samples of the high -T_{rm c} ceramic superconductors. To successfully study such a wide spectrum of materials, the charge transport instrumentation has evolved into multiple computer-controlled experimental arrangements which process data for temperature dependent ac and dc conductivity, thermoelectric power, critical current density, and other measurements, over the temperature range of 1.5 K to 400 K. The phthalocyanine-based molecular metals and conducting polymers exhibit some of the highest reported conductivities for environmentally stable organic conductors, and possess a unique structure which is inherently resistant to large structural transformations upon donor/acceptor doping. These properties are demonstrated primarily by results for Ni(Pc)(ClO_4) _{rm y} and { (Si(Pc)O) X_{rm y}}_{rm n}. The rigidly-enforced structure of the latter system of materials allows for controllable tuning of the band-filling and hence, the charge transport properties of an organic conductor, from insulating to metal-like behavior, without any major structural alterations of the polymeric backbone. Other types of polymeric samples for which results are presented consist of composite fibers formed from the rigid rod polymers, Kevlar and PBT, "alloyed" with the (Pc)-based conducting polymers, and new microlaminates formed by intercalating various conducting polymers into the van der Waals gap of inorganic, layered host materials. Significant success has been achieved in the fabrication of superconducting films of Y-Ba-Cu-O, Bi-Sr(Pb)-Ca-Cu -O, and Tl-Ba-Ca-Cu-O by organometallic chemical vapor deposition. Results are also presented for films prepared

  12. Transition in Electron Transport in a Cylindrical Hall Thruster

    SciTech Connect

    J.B. Parker, Y. Raitses, and N.J. Fisch

    2010-06-02

    Through the use of high-speed camera and Langmuir probe measurements in a cylindrical Hall thruster, we report the discovery of a rotating spoke of increased plasma density and light emission which correlates with increased electron transport across the magnetic field. As cathode electron emission is increased, a sharp transition occurs where the spoke disappears and electron transport decreases. This suggests that a significant fraction of the electron current might be directed through the spoke.

  13. Electronic and Ionic Transport Dynamics in Organolead Halide Perovskites.

    PubMed

    Li, Dehui; Wu, Hao; Cheng, Hung-Chieh; Wang, Gongming; Huang, Yu; Duan, Xiangfeng

    2016-07-26

    Ion migration has been postulated as the underlying mechanism responsible for the hysteresis in organolead halide perovskite devices. However, the electronic and ionic transport dynamics and how they impact each other in organolead halide perovskites remain elusive to date. Here we report a systematic investigation of the electronic and ionic transport dynamics in organolead halide perovskite microplate crystals and thin films using temperature-dependent transient response measurements. Our study reveals that thermally activated ionic and electronic conduction coexist in perovskite devices. The extracted activation energies suggest that the electronic transport is easier, but ions migrate harder in microplates than in thin films, demonstrating that the crystalline quality and grain boundaries can fundamentally modify electronic and ionic transport in perovskites. These findings offer valuable insight on the electronic and ionic transport dynamics in organolead halide perovskites, which is critical for optimizing perovskite devices with reduced hysteresis and improved stability and efficiency.

  14. The induction of microsomal electron transport enzymes.

    PubMed

    Waterman, M R; Estabrook, R W

    1983-01-01

    Liver endoplasmic reticulum contains as NADPH-dependent electron transport complex where the family of hemeproteins, termed cytochrome P-450, serve as catalysts for the oxidation of a variety of different organic chemicals. The content and inventory of the types of cytochrome P-450 is readily modified following in vivo treatment of animals with 'inducing agents' such as barbiturates, steroids and polycyclic hydrocarbons. Recent studies have applied the methods of molecular biology to evaluate changes in the transcription and translation of genomic information occurring concomitant with the initiation of synthesis of various types of cytochrome P-450. The ability to isolate unique cytochrome P-450 proteins and to prepare specific antibodies now permits the study of in vitro translation of mRNA and the preparation of specific cDNAs. The present review summarizes the historic background leading to current concepts of cytochrome P-450 induction and describes recent advances in our knowledge of the regulation of cytochrome P-450 synthesis in the liver.

  15. Electron injection and transport mechanism in organic devices based on electron transport materials

    NASA Astrophysics Data System (ADS)

    Khan, M. A.; Xu, Wei; Khizar-ul-Haq; Zhang, Xiao Wen; Bai, Yu; Jiang, X. Y.; Zhang, Z. L.; Zhu, W. Q.

    2008-11-01

    Electron injection and transport in organic devices based on electron transport (ET) materials, such as 4,7- diphyenyl-1,10-phenanthroline (Bathophenanthroline BPhen), 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline (Bathocuproine BCP) and bipyridyl oxadiazole compound 1,3-bis [2-(2,2'-bipyridin-6-yl)-1,3,4-oxadiazol-5-yl]benzene (Bpy-OXD), have been reported. The devices are composed of ITO/ET materials (BPhen, BCP Bpy-OXD)/cathodes, where cathodes = Au, Al and Ca. Current-voltage characteristics of each ET material are performed as a function of cathodes. We have found that Ca and Al exhibit quite different J-V characteristics compared with the gold (Au) cathode. The current is more than one order of magnitude higher for the Al cathode and more than three orders of magnitude higher for Ca compared with that of the Au cathode at ~8 V for all ET materials. This is because of the relatively low energy barrier at the organic/metal interface for Ca and Al cathodes. Electron-only devices with the Au cathode show that the electron transfer limitation is located at the organic/cathode interface and the Fowler-Nordheim mechanism is qualitatively consistent with experimental data at high voltages. With Ca and Al cathodes, electron conduction is preponderant and is bulk limited. A power law dependence J ~ Vm with m > 2 is consistent with the model of trap-charge limited conduction. The total electron trap density is estimated to be ~5 × 1018 cm-3. The critical voltage (Vc) is found to be ~45 V and is almost independent of the materials.

  16. Controlling ratchet transport via a finite kicked environment

    NASA Astrophysics Data System (ADS)

    Abdulack, S. A.; Beims, M. W.; Lopes, S. R.

    2016-12-01

    We study the effects of a finite kicked environment (bath) composed of N harmonic oscillators on the particle transport in a weakly dissipative quasisymmetric potential system. The small spatial asymmetry is responsible for the appearance of directed particle transport without a net bias, known as the ratchet transport. The whole dynamics is governed by a generalized map where dissipation in the system emerges due to its interaction with the kicked environment. Distinct spectral densities are imposed to the bath oscillators and play an essential role in such models. By changing the functional form of the spectral density, we observe that the transport can be optimized or even suppressed. We show evidences that the transport optimization is related to stability properties of periodic points of the ratchet system and depends on the bath temperature. In a Markovian approach, transport can be increased or suppressed depending on the bath influence.

  17. Electron Transport in Bacillus popilliae1

    PubMed Central

    Pepper, Rollin E.; Costilow, Ralph N.

    1965-01-01

    Pepper, Rollin E. (Michigan State University, East Lansing), and Ralph N. Costilow. Electron transport in Bacillus popilliae. J. Bacteriol. 89:271–276. 1965.—Bacillus popilliae was found to be unique among aerobic microorganisms in that it was deficient in a hydrogen peroxide-scavenging system. Neither catalase nor peroxidase was found. At the same time, a system for producing hydrogen peroxide during oxidation of reduced nicotinamide adenine dinucleotide (NADH2) was consistently present in the soluble fraction of extracts of cells from older cultures. Cells harvested from 9-hr cultures did not produce a significant amount of peroxide. The soluble NADH2 oxidase was apparently a flavoprotein, since it was stimulated by flavin nucleotides, insensitive to cyanide and azide, and inhibited by Atabrine. Also, difference spectra demonstrated the presence of a reducible flavin in the soluble fraction of cell extracts. The particulate fraction of cell extracts was shown by difference spectra to contain cytochrome b1; the strong inhibition of NADH2 oxidation by cyanide, azide, and carbon monoxide indicated that a terminal cytochrome oxidase was also present. This system was also flavin-dependent, since it was strongly inhibited by Atabrine. The specific activity of the NADH2 oxidase in the particulate fraction was lower in extracts of cells from older cultures than in those from exponentially growing cultures. Cytochrome c was not found in extracts of these cells. It is believed that the increased participation of the hydrogen peroxide-generating NADH2 oxidase in cells of older cultures may be responsible for the rapid loss in cell viability noted in stationary-phase cultures. PMID:14255689

  18. Magnetic turbulent electron transport in a reversed field pinch

    SciTech Connect

    Schoenberg, K.; Moses, R.

    1990-01-01

    A model of magnetic turbulent electron transport is presented. The model, based on the thermal conduction theory of Rechester and Rosenbluth, entails a Boltzmann description of electron dynamics in the long mean-free-path limit and quantitatively describes the salient features of superthermal electron measurements in the RFP edge plasma. Included are predictions of the mean superthermal electron energy, current density, and power flux asymmetry. A discussion of the transport model, the assumptions implicit in the model, and the relevance of this work to more general issue of magnetic turbulent transport in toroidal systems is presented. 32 refs., 3 figs.

  19. Operating systems in the air transportation environment.

    NASA Technical Reports Server (NTRS)

    Cherry, G. W.

    1971-01-01

    Consideration of the problems facing air transport at present, and to be expected in the future. In the Northeast Corridor these problems involve community acceptance, airway and airport congestion and delays, passenger acceptance, noise reduction, and improvements in low-density short-haul economics. In the development of a superior short-haul operating system, terminal-configured vs cruise-configured vehicles are evaluated. CTOL, STOL, and VTOL aircraft of various types are discussed. In the field of noise abatement, it is shown that flight procedural techniques are capable of supplementing ?quiet engine' technology.

  20. Bidirectional effect of magnetic field on electronic thermal transport of metals from all-electron first-principles calculations

    NASA Astrophysics Data System (ADS)

    Yang, Jia-Yue; Yue, Sheng-Ying; Hu, Ming

    2016-12-01

    Considerable discussions have occurred about the critical role played by free electrons in the transport of heat in pure metals. In principle, any environment that can influence the dynamical behaviors of electrons would have impact on electronic thermal conductivity (κel) of metals. Over the past decades, significant progress and comprehensive understanding have been gained from theoretical, as well as experimental, investigations by taking into account the effects of various conditions, typically temperature, impurities, strain, dimensionality, interface, etc. However, the effect of external magnetic field has received less attention. In this paper, the magnetic-field dependence of electron-phonon scattering, the electron's lifetime, and κel of representative metals (Al, Ni, and Nb) are investigated within the framework of all-electron spin-density functional theory. For Al and Ni, the induced magnetization vector field and difference in electron density under external magnetic-field aggregate toward the center of unit cell, leading to the enhanced electron-phonon scattering, the damped electron's lifetime, and thus the reduced κel. On the contrary, for Nb with strong intrinsic electron-phonon interaction, the electron's lifetime and κel slightly increase as external magnetic field is enhanced. This is mainly attributed to the separately distributed magnetization vector field and difference in electron density along the corner of unit cell. This paper sheds light on the origin of influence of external magnetic field on κel for pure metals and offers a new route for robust manipulation of electronic thermal transport via applying external magnetic field.

  1. 500(deg)C electronics for harsh environments

    NASA Technical Reports Server (NTRS)

    Sadwick, Laurence P.; Hwu, R. Jennifer; Chern, J. H. Howard; Lin, Ching-Hsu; Castillo, Linda Del; Johnson, Travis

    2005-01-01

    Solid state vacuum devices (SSVDs) are a relatively new class of electronic devices. Innosys is a leading producer of high frequency SSVDs for a number of applications, including RF communications. SSVDs combine features inherent to both solid state and vacuum transistors. Electron transport can be by solid state or vacuum or both. The focus of this talk is on thermionic SSVDs, in which the primary vacuum transport is by thermionically liberated electron emission.

  2. Electron Transport in Graphene From a Diffusion-Drift Perspective

    DTIC Science & Technology

    2010-02-24

    IEEE TRANSACTIONS ON ELECTRON DEVICES, VOL. 57, NO. 3, MARCH 2010 681 Electron Transport in Graphene From a Diffusion-Drift Perspective Mario G...Ancona,Member, IEEE Abstract—A diffusion–drift treatment of electron and hole transport in macroscopic graphene is presented. The various ma- terial...applied to a variety of situations involving field-effect devices that are of potential technological interest. Both single and multilayer graphene are

  3. Lunar Dust Grain Charging by Electron Impact: Complex Role of Secondary Electron Emissions in Space Environments

    NASA Astrophysics Data System (ADS)

    Abbas, M. M.; Tankosic, D.; Craven, P. D.; LeClair, A. C.; Spann, J. F.

    2010-08-01

    Dust grains in various astrophysical environments are generally charged electrostatically by photoelectric emissions with radiation from nearby sources, or by electron/ion collisions by sticking or secondary electron emissions (SEEs). The high vacuum environment on the lunar surface leads to some unusual physical and dynamical phenomena involving dust grains with high adhesive characteristics, and levitation and transportation over long distances. Knowledge of the dust grain charges and equilibrium potentials is important for understanding a variety of physical and dynamical processes in the interstellar medium, and heliospheric, interplanetary/planetary, and lunar environments. It has been well recognized that the charging properties of individual micron-/submicron-size dust grains are expected to be substantially different from the corresponding values for bulk materials. In this paper, we present experimental results on the charging of individual 0.2-13 μm size dust grains selected from Apollo 11 and 17 dust samples, and spherical silica particles by exposing them to mono-energetic electron beams in the 10-200 eV energy range. The dust charging process by electron impact involving the SEEs discussed is found to be a complex charging phenomenon with strong particle size dependence. The measurements indicate substantial differences between the polarity and magnitude of the dust charging rates of individual small-size dust grains, and the measurements and model properties of corresponding bulk materials. A more comprehensive plan of measurements of the charging properties of individual dust grains for developing a database for realistic models of dust charging in astrophysical and lunar environments is in progress.

  4. Lunary Dust Grain Charging by Electron Impact: Complex Role of Secondary Electron Emissions in Space Environments

    NASA Technical Reports Server (NTRS)

    Abbas, M. M.; Tankosic, D.; Crave, P. D.; LeClair, A.; Spann, J. F.

    2010-01-01

    Dust grains in various astrophysical environments are generally charged electrostatically by photoelectric emissions with radiation from nearby sources, or by electron/ion collisions by sticking or secondary electron emissions (SEES). The high vacuum environment on the lunar surface leads to some unusual physical and dynamical phenomena involving dust grains with high adhesive characteristics, and levitation and transportation over long distances. Knowledge of the dust grain charges and equilibrium potentials is important for understanding a variety of physical and dynamical processes in the interstellar medium, and heliospheric, interplanetary/ planetary, and lunar environments. It has been well recognized that the charging properties of individual micron-/submicron-size dust grains are expected to be substantially different from the corresponding values for bulk materials. In this paper, we present experimental results on the charging of individual 0.2-13 m size dust grains selected from Apollo 11 and 17 dust samples, and spherical silica particles by exposing them to mono-energetic electron beams in the 10-200 eV energy range. The dust charging process by electron impact involving the SEES discussed is found to be a complex charging phenomenon with strong particle size dependence. The measurements indicate substantial differences between the polarity and magnitude of the dust charging rates of individual small-size dust grains, and the measurements and model properties of corresponding bulk materials. A more comprehensive plan of measurements of the charging properties of individual dust grains for developing a database for realistic models of dust charging in astrophysical and lunar environments is in progress.

  5. LUNAR DUST GRAIN CHARGING BY ELECTRON IMPACT: COMPLEX ROLE OF SECONDARY ELECTRON EMISSIONS IN SPACE ENVIRONMENTS

    SciTech Connect

    Abbas, M. M.; Craven, P. D.; LeClair, A. C.; Spann, J. F.; Tankosic, D.

    2010-08-01

    Dust grains in various astrophysical environments are generally charged electrostatically by photoelectric emissions with radiation from nearby sources, or by electron/ion collisions by sticking or secondary electron emissions (SEEs). The high vacuum environment on the lunar surface leads to some unusual physical and dynamical phenomena involving dust grains with high adhesive characteristics, and levitation and transportation over long distances. Knowledge of the dust grain charges and equilibrium potentials is important for understanding a variety of physical and dynamical processes in the interstellar medium, and heliospheric, interplanetary/planetary, and lunar environments. It has been well recognized that the charging properties of individual micron-/submicron-size dust grains are expected to be substantially different from the corresponding values for bulk materials. In this paper, we present experimental results on the charging of individual 0.2-13 {mu}m size dust grains selected from Apollo 11 and 17 dust samples, and spherical silica particles by exposing them to mono-energetic electron beams in the 10-200 eV energy range. The dust charging process by electron impact involving the SEEs discussed is found to be a complex charging phenomenon with strong particle size dependence. The measurements indicate substantial differences between the polarity and magnitude of the dust charging rates of individual small-size dust grains, and the measurements and model properties of corresponding bulk materials. A more comprehensive plan of measurements of the charging properties of individual dust grains for developing a database for realistic models of dust charging in astrophysical and lunar environments is in progress.

  6. Electrokinesis is a microbial behavior that requires extracellular electron transport

    SciTech Connect

    Harris, Howard W.; El-Naggar, Mohamed Y.; Bretschger, Orianna; Ward, Melissa J.; Romine, Margaret F.; Obraztsova, Anna; Nealson, Kenneth H.

    2010-01-05

    Shewanella species are widespread in nature, enjoying a cosmopolitan distribution in marine,freshwater, sedimentary and soil environments (1), and have attracted considerable attention in recent years because of their ability to reduce an extensive number of different electron 3 acceptors, including the solid (oxy)hydroxides of iron and manganese, such as Fe(OH)3 and MnO2, using one or more proposed mechanisms of extracellular electron transport (EET) (2, 3). The EET ability of Shewanella species is consistent with their ability to generate electric current in microbial fuel cells in the absence of exogenous electron shuttles (4). Various strategies of extracellular electron transfer have been proposed in metal-reducing microbes, including naturally-occurring (2) or biogenic (5-7) soluble mediators that ‘shuttle’ electrons from cells to acceptors, as well as direct transfer using multiheme cytochromes located on the cell exterior (8) and transfer via conductive nanowires (9-11). S. oneidensis MR-1 features several proteins that are involved with the transport of electrons to the exterior of the cell where they play an important role with regard to the reduction of solid electron acceptors such as metal oxides. These include two outer-membrane decaheme c-type cytochromes (MtrC and OmcA), a membrane spanning protein (MtrB), and two periplasmic multi-heme c-type cytochromes (MtrA and CymA). Deletion of the genes encoding any of these proteins leads to phenotypes that are greatly inhibited with regard to metal-oxide reduction and current production in microbial fuel cells (MFCs) (12, 13). The mutation of genes that code for proteins involved in the movement of cytochromes to the outer membrane also results in loss of metal-reducing phenotypes (13). The shewanellae are highly motile, by virtue of a single polar flagellum, and individual S. oneidensis MR-1 cells have been tracked swimming at speeds of up to, and sometimes over, 100 μm/sec, although the average

  7. Kinetic theory of transport processes in partially ionized reactive plasma, II: Electron transport properties

    NASA Astrophysics Data System (ADS)

    Zhdanov, V. M.; Stepanenko, A. A.

    2016-11-01

    The previously obtained in (Zhdanov and Stepanenko, 2016) general transport equations for partially ionized reactive plasma are employed for analysis of electron transport properties in molecular and atomic plasmas. We account for both elastic and inelastic interaction channels of electrons with atoms and molecules of plasma and also the processes of electron impact ionization of neutral particles and three-body ion-electron recombination. The system of scalar transport equations for electrons is discussed and the expressions for non-equilibrium corrections to electron ionization and recombination rates and the diagonal part of the electron pressure tensor are derived. Special attention is paid to analysis of electron energy relaxation during collisions with plasma particles having internal degrees of freedom and the expression for the electron coefficient of inelastic energy losses is deduced. We also derive the expressions for electron vector and tensorial transport fluxes and the corresponding transport coefficients for partially ionized reactive plasma, which represent a generalization of the well-known results obtained by Devoto (1967). The results of numerical evaluation of contribution from electron inelastic collisions with neutral particles to electron transport properties are presented for a series of molecular and atomic gases.

  8. Terahertz electromodulation spectroscopy of electron transport in GaN

    NASA Astrophysics Data System (ADS)

    Engelbrecht, S. G.; Arend, T. R.; Zhu, T.; Kappers, M. J.; Kersting, R.

    2015-03-01

    Time-resolved terahertz (THz) electromodulation spectroscopy is applied to investigate the high-frequency transport of electrons in gallium nitride at different doping concentrations and densities of threading dislocations. At THz frequencies, all structures reveal Drude transport. The analysis of the spectral response provides the fundamental transport properties, such as the electron scattering time and the electrons' conductivity effective mass. We observe the expected impact of ionized-impurity scattering and that scattering at threading dislocations only marginally affects the high-frequency mobility.

  9. Terahertz electromodulation spectroscopy of electron transport in GaN

    SciTech Connect

    Engelbrecht, S. G.; Arend, T. R.; Kersting, R.; Zhu, T.; Kappers, M. J.

    2015-03-02

    Time-resolved terahertz (THz) electromodulation spectroscopy is applied to investigate the high-frequency transport of electrons in gallium nitride at different doping concentrations and densities of threading dislocations. At THz frequencies, all structures reveal Drude transport. The analysis of the spectral response provides the fundamental transport properties, such as the electron scattering time and the electrons' conductivity effective mass. We observe the expected impact of ionized-impurity scattering and that scattering at threading dislocations only marginally affects the high-frequency mobility.

  10. A deterministic computational model for the two dimensional electron and photon transport

    NASA Astrophysics Data System (ADS)

    Badavi, Francis F.; Nealy, John E.

    2014-12-01

    A deterministic (non-statistical) two dimensional (2D) computational model describing the transport of electron and photon typical of space radiation environment in various shield media is described. The 2D formalism is casted into a code which is an extension of a previously developed one dimensional (1D) deterministic electron and photon transport code. The goal of both 1D and 2D codes is to satisfy engineering design applications (i.e. rapid analysis) while maintaining an accurate physics based representation of electron and photon transport in space environment. Both 1D and 2D transport codes have utilized established theoretical representations to describe the relevant collisional and radiative interactions and transport processes. In the 2D version, the shield material specifications are made more general as having the pertinent cross sections. In the 2D model, the specification of the computational field is in terms of a distance of traverse z along an axial direction as well as a variable distribution of deflection (i.e. polar) angles θ where -π/2<θ<π/2, and corresponding symmetry is assumed for the range of azimuth angles (0<φ<2π). In the transport formalism, a combined mean-free-path and average trajectory approach is used. For candidate shielding materials, using the trapped electron radiation environments at low Earth orbit (LEO), geosynchronous orbit (GEO) and Jupiter moon Europa, verification of the 2D formalism vs. 1D and an existing Monte Carlo code are presented.

  11. Molecular electronics: some views on transport junctions and beyond.

    PubMed

    Joachim, Christian; Ratner, Mark A

    2005-06-21

    The field of molecular electronics comprises a fundamental set of issues concerning the electronic response of molecules as parts of a mesoscopic structure and a technology-facing area of science. We will overview some important aspects of these subfields. The most advanced ideas in the field involve the use of molecules as individual logic or memory units and are broadly based on using the quantum state space of the molecule. Current work in molecular electronics usually addresses molecular junction transport, where the molecule acts as a barrier for incoming electrons: This is the fundamental Landauer idea of "conduction as scattering" generalized to molecular junction structures. Another point of view in terms of superexchange as a guiding mechanism for coherent electron transfer through the molecular bridge is discussed. Molecules generally exhibit relatively strong vibronic coupling. The last section of this overview focuses on vibronic effects, including inelastic electron tunneling spectroscopy, hysteresis in junction charge transport, and negative differential resistance in molecular transport junctions.

  12. Four papers on transportation and the environment

    NASA Astrophysics Data System (ADS)

    Roth, Kevin Daniel

    The main essay of this thesis, found in the first chapter, examines how two policies that are a priori equivalent, fuel economy standards and feebates, interact differently with complementary policies that also attempt to improve fuel economy. To examine these interactions I build a general equilibrium model of the automobile market that allows manufacturers to trade off horsepower, weight, and fuel economy of vehicles along a production possibility frontier (PPF). I also estimate household demand for vehicles and miles for a simulation model that includes the used car and scrappage markets. This model allows me to simulate the interaction of a research and development policy that increases the PPF of domestic firms, or a tax credit that increases demand for efficient vehicles, with either a CAFE standard or feebate. I find that vehicle emissions increase under all these interactions but the effects are muted under the feebate because it allows fuel economy to improve by 0.60% to 1.88%, while CAFE, by targeting an average fuel economy, will always offset these uncoordinated complementary policies. The second essay examines transportation systems with unpriced congestion where single-occupant low-emission vehicles are allowed into high occupancy vehicle (HOV) lanes to encourage their adoption exacerbates congestion costs for carpoolers. The resulting welfare effects of the policy are negative, with environmental benefits overwhelmingly dominated by the increased congestion costs. Exploiting the introduction of the Clean Air Vehicle Stickers policy in California with a regression discontinuity design, our results imply a best-case cost of 124 per ton of reductions in greenhouse gases, 606,000 dollars per ton of nitrogen oxides reduction, and $505,000 dollars per ton of hydrocarbon reduction, exceeding those of other options readily available to policymakers. The third essay examines the 'Energy Paradox.' From previous literature, it can be found that consumers tend

  13. Analysis of electron transport in the plasma of thermionic converters

    SciTech Connect

    Stoenescu, M.L.; Heinicke, P.H.

    1980-03-01

    Electron transport coefficients of a gaseous ensemble are expressed analytically as function of density, and are expressed analytically as function of temperature up to an unknown function which has to be evaluated for each specific electron-neutral atom cross section. In order to complete the analytical temperature dependence one may introduce a polynomial expansion of the function or one may derive the temperature dependence of a set of coefficients, numbering thirteen for a third approximation transport evaluation, which completely determine the transport coefficients. The latter approach is used for determining the electron transport coefficients of a cesium plasma for any ion neutral composition and any temperature between 500/sup 0/K and 3500/sup 0/K. The relation between the transport coefficients of a fully and partly ionized gas is readily available and shows that, in the classical formalism, electron-ion and electron-neutral resistivities are not additive. The present form of the transport coefficients makes possible an accurate numerical integration of transport equations eliminating lengthy computations which are frequently inaccessible. It thus provides a detailed knowledge of spatial distribution of particle and energy transport and makes possible the determination of one of the three internal voltage drops, surface barrier, sheath and plasma, which are linked together experimentally by current density versus voltage characteristics of thermionic converters.

  14. Fast electron generation and transport in a turbulent, magnetized plasma

    SciTech Connect

    Stoneking, Matthew Randall

    1994-05-01

    The nature of fast electron generation and transport in the Madison Symmetric Torus (MST) reversed field pinch (RFP) is investigated using two electron energy analyzer (EEA) probes and a thermocouple calorimeter. The parallel velocity distribution of the fast electron population is well fit by a drifted Maxwellian distribution with temperature of about 100 eV and drift velocity of about 2 x 106 m/s. Cross-calibration of the EEA with the calorimeter provides a measurement of the fast electron perpendicular temperature of 30 eV, much lower than the parallel temperature, and is evidence that the kinetic dynamo mechanism (KDT) is not operative in MST. The fast electron current is found to match to the parallel current at the edge, and the fast electron density is about 4 x 1011 cm-3 independent of the ratio of the applied toroidal electric field to the critical electric field for runaways. First time measurements of magnetic fluctuation induced particle transport are reported. By correlating electron current fluctuations with radial magnetic fluctuations the transported flux of electrons is found to be negligible outside r/a~0.9, but rises the level of the expected total particle losses inside r/a~0.85. A comparison of the measured diffusion coefficient is made with the ausilinear stochastic diffusion coefficient. Evidence exists that the reduction of the transport is due to the presence of a radial ambipolar electric field of magnitude 500 V/m, that acts to equilibrate the ion and electron transport rates. The convective energy transport associated with the measured particle transport is large enough to account for the observed magnetic fluctuation induced energy transport in MST.

  15. Hot electron transport and current sensing

    NASA Astrophysics Data System (ADS)

    Abraham, Mathew Cheeran

    The effect of hot electrons on momentum scattering rates in a two-dimensional electron gas is critically examined. It is shown that with hot electrons it is possible to explore the temperature dependence of individual scattering mechanisms not easily probed under equilibrium conditions; both the Bloch-Gruneisen (BG) phonon scattering phenomena and the reduction in impurity scattering are clearly observed. The theoretical calculations are consistent with the results obtained from hot electrons experiments. As a function of bias current, a resistance peak is formed in a 2DEG if the low temperature impurity limited mobilities muI( T = 0) is comparable to muph(TBG ) the phonon limited mobility at the critical BG temperature. In this case, as the bias current is increased, the electron temperature Te rises due to Joule heating and the rapid increase in phonon scattering can be detected before the effect of the reduction in impurity scattering sets in. If muI(T = 0) << muph(TBG), there is no peak in resistance because the impurity scattering dominates sufficiently and its reduction has a much stronger effect on the total resistance than the rise in phonon scattering. Furthermore, knowing the momentum relaxation rates allows us to analyze the possible interplay between electron-electron and electron-boundary scattering. The prediction that a Knudsen to Poiseuille (KP) transition similar to that of a classical gas can occur in electron flow [26] is examined for the case of a wire defined in a 2DEG. Concurrently, an appropriate current imaging technique to detect this transition is sought. A rigorous evaluation of magnetic force microscopy (MFM) as a possible candidate to detect Poiseuille electronic flow was conducted, and a method that exploits the mechanical resonance of the MFM cantilever was implemented to significantly improve its current sensitivity.

  16. Electron transport-dependent taxis in Rhodobacter sphaeroides.

    PubMed

    Gauden, D E; Armitage, J P

    1995-10-01

    Rhodobacter sphaeroides showed chemotaxis to the terminal electron acceptors oxygen and dimethyl sulfoxide, and the responses to these effectors were shown to be influenced by the relative activities of the different electron transport pathways. R. sphaeroides cells tethered by their flagella showed a step-down response to a decrease in the oxygen or dimethyl sulfoxide concentration when using them as terminal acceptors. Bacteria using photosynthetic electron transport, however, showed a step-down response to oxygen addition. Addition of the proton ionophore carbonyl cyanide 4-trifluoromethoxyphenylhydrazone did not cause a transient behavioral response, although it decreased the electrochemical proton gradient (delta p) and increased the rate of electron transport. However, removal of the ionophore, which caused an increase in delta p and a decrease in the electron transport rate, resulted in a step-down response. Together, these data suggest that behavioral responses of R. sphaeroides to electron transport effectors are caused by changes in the rate of electron transport rather than changes in delta p.

  17. Non-nuclear Electron Transport Channels in Hollow Molecules

    SciTech Connect

    Zhao, Jin; Petek, Hrvoje

    2014-08-15

    Electron transport in inorganic semiconductors and metals occurs through delocalized bands formed by overlapping electron orbitals. Strong correlation of electronic wave functions with the ionic cores couples the electron and lattice motions, leading to efficient interaction and scattering that degrades coherent charge transport. By contrast, unoccupied electronic states at energies near the vacuum level with diffuse molecular orbitals may form nearly-free-electron bands with density maxima in non-nuclear interstitial voids, which are subject to weaker electron-phonon interaction. The position of such bands typically above the frontier orbitals, however, renders them unstable with respect to electronic interband relaxation and therefore unsuitable for charge transport. Through electronic-structure calculations, we engineer stable, non-nuclear, nearly-free-electron conduction channels in low-dimensional molecular materials by tailoring their electrostatic and polarization potentials. We propose quantum structures of graphane-derived Janus molecular sheets with spatially isolated conducting and insulating regions that potentially exhibit emergent electronic properties, as a paradigm for molecular-scale non-nuclear charge conductors; we also describe tuning of their electronic properties by application of external fields and calculate their electron–acoustic-phonon interaction.

  18. Numerical evidence for robustness of environment-assisted quantum transport.

    PubMed

    Shabani, A; Mohseni, M; Rabitz, H; Lloyd, S

    2014-04-01

    Recent theoretical studies show that decoherence process can enhance transport efficiency in quantum systems. This effect is known as environment-assisted quantum transport (ENAQT). The role of ENAQT in optimal quantum transport is well investigated; however, it is less known how robust ENAQT is with respect to variations in the system or its environment characteristic. Toward answering this question, we simulated excitonic energy transfer in Fenna-Matthews-Olson photosynthetic complex. We found that ENAQT is robust with respect to many relevant parameters of environmental interactions and Frenkel-exciton Hamiltonians, including reorganization energy, bath-frequency cutoff, temperature, initial excitations, dissipation rate, trapping rate, disorders, and dipole moments orientations. Our study suggests that the ENAQT phenomenon can be exploited in robust design of highly efficient quantum transport systems.

  19. Transport of electrons in lead oxide studied by CELIV technique

    NASA Astrophysics Data System (ADS)

    Semeniuk, O.; Juska, G.; Oelerich, J. O.; Jandieri, K.; Baranovskii, S. D.; Reznik, A.

    2017-01-01

    Although polycrystalline lead oxide (PbO) has a long history of application in optoelectronics and imaging, the transport mechanism for electrons in this material has not yet been clarified. Using the photo-generated charge extraction by linear increasing voltage (photo-CELIV) technique, we provide the temperature- and field-dependences of electron mobility in poly-PbO. It is found that electrons undergo dispersive transport, i.e. their mobility decreases in the course of time. Multiple trapping of electrons from the conduction band into the developed band tail is revealed as the dominant transport mechanism. This differs dramatically from the dispersive transport of holes in the same material, dominated by topological factors and not by energy disorder.

  20. Large electron screening effect in different environments

    SciTech Connect

    Cvetinović, Aleksandra Lipoglavšek, Matej; Markelj, Sabina; Vesić, Jelena

    2015-10-15

    Electron screening effect was studied in the {sup 1}H({sup 7}Li,α){sup 4}He, {sup 1}H({sup 11}B,α){sup 4}He and {sup 1}H({sup 19}F,αγ){sup 16}O reactions in inverse kinematics on different hydrogen implanted targets. Results show large electron screening potentials strongly dependent on the proton number Z of the projectile.

  1. Large electron screening effect in different environments

    NASA Astrophysics Data System (ADS)

    Cvetinović, Aleksandra; Lipoglavsek, Matej; Markelj, Sabina; Vesić, Jelena

    2016-05-01

    Electron screening effect was studied on different hydrogen containing targets with the 7Li, 11B and 19F ion beams. Results show large electron screening potentials strongly dependent on the proton number Z of the projectile. The largest ever measured screening potential with the value about a factor of 50 above the calculations from the model in adiabatic limit was observed in the graphite target containing hydrogen as an impurity.

  2. Transport of runaway and thermal electrons due to magnetic microturbulence

    SciTech Connect

    Mynick, H.E.; Strachan, J.D.

    1981-04-01

    The ratio of the runaway electron confinement to thermal electron energy confinement is derived for tokamaks where both processes are determined by free streaming along stochastic magnetic field lines. The runaway electron confinement is enhanced at high runaway electron energies due to phase averaging over the magnetic perturbations when the runaway electron drift surfaces are displaced from the magnetic surfaces. Comparison with experimental data from LT-3, Ormak, PLT, ST, and TM-3 indicates that magnetic stochasticity may explain the relative transport rates of runaways and thermal electron energy.

  3. Simulation of electron thermal transport in H-mode discharges

    NASA Astrophysics Data System (ADS)

    Rafiq, T.; Pankin, A. Y.; Bateman, G.; Kritz, A. H.; Halpern, F. D.

    2009-03-01

    Electron thermal transport in DIII-D H-mode tokamak plasmas [J. L. Luxon, Nucl. Fusion 42, 614 (2002)] is investigated by comparing predictive simulation results for the evolution of electron temperature profiles with experimental data. The comparison includes the entire profile from the magnetic axis to the bottom of the pedestal. In the simulations, carried out using the automated system for transport analysis (ASTRA) integrated modeling code, different combinations of electron thermal transport models are considered. The combinations include models for electron temperature gradient (ETG) anomalous transport and trapped electron mode (TEM) anomalous transport, as well as a model for paleoclassical transport [J. D. Callen, Nucl. Fusion 45, 1120 (2005)]. It is found that the electromagnetic limit of the Horton ETG model [W. Horton et al., Phys. Fluids 31, 2971 (1988)] provides an important contribution near the magnetic axis, which is a region where the ETG mode in the GLF23 model [R. E. Waltz et al., Phys. Plasmas 4, 2482 (1997)] is below threshold. In simulations of DIII-D discharges, the observed shape of the H-mode edge pedestal is produced when transport associated with the TEM component of the GLF23 model is suppressed and transport given by the paleoclassical model is included. In a study involving 15 DIII-D H-mode discharges, it is found that with a particular combination of electron thermal transport models, the average rms deviation of the predicted electron temperature profile from the experimental profile is reduced to 9% and the offset to -4%.

  4. Characterizing transport through a crowded environment with different obstacle sizes.

    PubMed

    Ellery, Adam J; Simpson, Matthew J; McCue, Scott W; Baker, Ruth E

    2014-02-07

    Transport through crowded environments is often classified as anomalous, rather than classical, Fickian diffusion. Several studies have sought to describe such transport processes using either a continuous time random walk or fractional order differential equation. For both these models the transport is characterized by a parameter α, where α = 1 is associated with Fickian diffusion and α < 1 is associated with anomalous subdiffusion. Here, we simulate a single agent migrating through a crowded environment populated by impenetrable, immobile obstacles and estimate α from mean squared displacement data. We also simulate the transport of a population of such agents through a similar crowded environment and match averaged agent density profiles to the solution of a related fractional order differential equation to obtain an alternative estimate of α. We examine the relationship between our estimate of α and the properties of the obstacle field for both a single agent and a population of agents; we show that in both cases, α decreases as the obstacle density increases, and that the rate of decrease is greater for smaller obstacles. Our work suggests that it may be inappropriate to model transport through a crowded environment using widely reported approaches including power laws to describe the mean squared displacement and fractional order differential equations to represent the averaged agent density profiles.

  5. RHIC electron lens beam transport system design considerations

    SciTech Connect

    Gu, X.; Pikin, A.; Okamura, M.; Fischer, W.; Luo, Y.; Gupta, R.; Hock, J.; Jain, A.; Raparia, D.

    2010-10-01

    To apply head-on beam-beam compensation for RHIC, two electron lenses are designed and will be installed at IP10. Electron beam transport system is one of important subsystem, which is used to transport electron beam from electron gun side to collector side. This system should be able to change beam size inside superconducting magnet and control beam position with 5 mm in horizontal and vertical plane. Some other design considerations for this beam transport system are also reported in this paper. The head-on beam-beam effect is one of important nonlinear source in storage ring and linear colliders, which have limited the luminosity improvement of many colliders, such as SppS, Tevatron and RHIC. In order to enhance the performance of colliders, beam-beam effects can be compensated with direct space charge compensation, indirect space charge compensation or betatron phase cancellation scheme. Like other colliders, indirect space charge compensation scheme (Electron Lens) was also proposed for Relativistic Heavy Ion Collider (RHIC) beam-beam compensation at Brookhaven National Laboratory. The two similar electron lenses are located in IR10 between the DX magnets. One RHIC electron lens consists of one DC electron gun, one superconducting magnet, one electron collector and beam transport system.

  6. SUPPRESSION OF ENERGETIC ELECTRON TRANSPORT IN FLARES BY DOUBLE LAYERS

    SciTech Connect

    Li, T. C.; Drake, J. F.; Swisdak, M.

    2012-09-20

    During flares and coronal mass ejections, energetic electrons from coronal sources typically have very long lifetimes compared to the transit times across the systems, suggesting confinement in the source region. Particle-in-cell simulations are carried out to explore the mechanisms of energetic electron transport from the corona to the chromosphere and possible confinement. We set up an initial system of pre-accelerated hot electrons in contact with ambient cold electrons along the local magnetic field and let it evolve over time. Suppression of transport by a nonlinear, highly localized electrostatic electric field (in the form of a double layer) is observed after a short phase of free-streaming by hot electrons. The double layer (DL) emerges at the contact of the two electron populations. It is driven by an ion-electron streaming instability due to the drift of the back-streaming return current electrons interacting with the ions. The DL grows over time and supports a significant drop in temperature and hence reduces heat flux between the two regions that is sustained for the duration of the simulation. This study shows that transport suppression begins when the energetic electrons start to propagate away from a coronal acceleration site. It also implies confinement of energetic electrons with kinetic energies less than the electrostatic energy of the DL for the DL lifetime, which is much longer than the electron transit time through the source region.

  7. Nano-structured electron transporting materials for perovskite solar cells

    NASA Astrophysics Data System (ADS)

    Liu, Hefei; Huang, Ziru; Wei, Shiyuan; Zheng, Lingling; Xiao, Lixin; Gong, Qihuang

    2016-03-01

    Organic-inorganic hybrid perovskite solar cells have been developing rapidly in the past several years, and their power conversion efficiency has reached over 20%, nearing that of polycrystalline silicon solar cells. Because the diffusion length of the hole in perovskites is longer than that of the electron, the performance of the device can be improved by using an electron transporting layer, e.g., TiO2, ZnO and TiO2/Al2O3. Nano-structured electron transporting materials facilitate not only electron collection but also morphology control of the perovskites. The properties, morphology and preparation methods of perovskites are reviewed in the present article. A comprehensive understanding of the relationship between the structure and property will benefit the precise control of the electron transporting process and thus further improve the performance of perovskite solar cells.

  8. Nano-structured electron transporting materials for perovskite solar cells.

    PubMed

    Liu, Hefei; Huang, Ziru; Wei, Shiyuan; Zheng, Lingling; Xiao, Lixin; Gong, Qihuang

    2016-03-28

    Organic-inorganic hybrid perovskite solar cells have been developing rapidly in the past several years, and their power conversion efficiency has reached over 20%, nearing that of polycrystalline silicon solar cells. Because the diffusion length of the hole in perovskites is longer than that of the electron, the performance of the device can be improved by using an electron transporting layer, e.g., TiO2, ZnO and TiO2/Al2O3. Nano-structured electron transporting materials facilitate not only electron collection but also morphology control of the perovskites. The properties, morphology and preparation methods of perovskites are reviewed in the present article. A comprehensive understanding of the relationship between the structure and property will benefit the precise control of the electron transporting process and thus further improve the performance of perovskite solar cells.

  9. Computer modeling of electron and proton transport in chloroplasts.

    PubMed

    Tikhonov, Alexander N; Vershubskii, Alexey V

    2014-07-01

    Photosynthesis is one of the most important biological processes in biosphere, which provides production of organic substances from atmospheric CO2 and water at expense of solar energy. In this review, we contemplate computer models of oxygenic photosynthesis in the context of feedback regulation of photosynthetic electron transport in chloroplasts, the energy-transducing organelles of the plant cell. We start with a brief overview of electron and proton transport processes in chloroplasts coupled to ATP synthesis and consider basic regulatory mechanisms of oxygenic photosynthesis. General approaches to computer simulation of photosynthetic processes are considered, including the random walk models of plastoquinone diffusion in thylakoid membranes and deterministic approach to modeling electron transport in chloroplasts based on the mass action law. Then we focus on a kinetic model of oxygenic photosynthesis that includes key stages of the linear electron transport, alternative pathways of electron transfer around photosystem I (PSI), transmembrane proton transport and ATP synthesis in chloroplasts. This model includes different regulatory processes: pH-dependent control of the intersystem electron transport, down-regulation of photosystem II (PSII) activity (non-photochemical quenching), the light-induced activation of the Bassham-Benson-Calvin (BBC) cycle. The model correctly describes pH-dependent feedback control of electron transport in chloroplasts and adequately reproduces a variety of experimental data on induction events observed under different experimental conditions in intact chloroplasts (variations of CO2 and O2 concentrations in atmosphere), including a complex kinetics of P700 (primary electron donor in PSI) photooxidation, CO2 consumption in the BBC cycle, and photorespiration. Finally, we describe diffusion-controlled photosynthetic processes in chloroplasts within the framework of the model that takes into account complex architecture of

  10. Interactive design environment transportation channel of relativistic charged particle beams

    NASA Astrophysics Data System (ADS)

    Osadchuk, I. O.; Averyanov, G. P.; Budkin, V. A.

    2017-01-01

    Considered a modern implementation of a computer environment for the design of channels of transportation of high-energy charged particle beams. The environment includes a software package for the simulation of the dynamics of charged particles in the channel, operating means for changing parameters of the channel, the elements channel optimization and processing of the output characteristics of the beam with the graphical output the main output parameters.

  11. Conditioner for a helically transported electron beam

    SciTech Connect

    Wang, C.

    1992-05-01

    The kinetic theory is developed to investigate a conditioner for a helically imported electron beam. Linear expressions for axial velocity spread are derived. Numerical simulation is used to check the theoretical results and examine nonlinear aspects of the conditioning process. The results show that in the linear regime the action of the beam conditioner on a pulsed beam mainly depends on the phase at which the beam enters the conditioner and depends only slightly on the operating wavelength. In the nonlinear regime, however, the action of the conditioner strongly depends on the operating wavelength and only slightly upon the entrance phase. For a properly chosen operating wavelength, a little less than the electron`s relativistic cyclotron wavelength, the conditioner can decrease the axial velocity spread of a pulsed beam down to less than one-third of its initial value.

  12. Coherent electron transport in a helical nanotube

    NASA Astrophysics Data System (ADS)

    Liang, Guo-Hua; Wang, Yong-Long; Du, Long; Jiang, Hua; Kang, Guang-Zhen; Zong, Hong-Shi

    2016-09-01

    The quantum dynamics of carriers bound to helical tube surfaces is investigated in a thin-layer quantization scheme. By numerically solving the open-boundary Schrödinger equation in curvilinear coordinates, geometric effect on the coherent transmission spectra is analysed in the case of single propagating mode as well as multimode. It is shown that, the coiling endows the helical nanotube with different transport properties from a bent cylindrical surface. Fano resonance appears as a purely geometric effect in the conductance, the corresponding energy of quasibound state is obviously influenced by the torsion and length of the nanotube. We also find new plateaus in the conductance. The transport of double-degenerate mode in this geometry is reminiscent of the Zeeman coupling between the magnetic field and spin angular momentum in quasi-one-dimensional structure.

  13. Student Performance in an Electronic Text Environment.

    ERIC Educational Resources Information Center

    Friedman, Edward A.; And Others

    1989-01-01

    Describes a project conducted at Stevens Institute of Technology to develop and test the applicability of full-text electronic databases and full-text retrieval technology for use in undergraduate humanities education. The creation of a machine-readable database on Galileo is described, student reactions are discussed, and further work is…

  14. Electronic transport and scattering times in tungsten-decorated graphene

    NASA Astrophysics Data System (ADS)

    Elias, Jamie A.; Henriksen, Erik A.

    2017-02-01

    The electronic transport properties of a monolayer graphene device have been studied before and after the deposition of a dilute coating of tungsten adatoms on the surface. For coverages up to 2.5% of a monolayer, we find tungsten adatoms simultaneously donate electrons to graphene and reduce the carrier mobility, impacting the zero- and finite-field transport properties. Two independent transport analyses suggest the adatoms lie nearly 1 nm above the surface. The presence of adatoms is also seen to impact the low-field magnetoresistance, altering the signatures of weak localization.

  15. Electron transport through nuclear pasta in magnetized neutron stars

    NASA Astrophysics Data System (ADS)

    Yakovlev, D. G.

    2015-10-01

    We present a simple model for electron transport in a possible layer of exotic nuclear clusters (in the so-called nuclear pasta layer) between the crust and liquid core of a strongly magnetized neutron star. The electron transport there can be strongly anisotropic and gyrotropic. The anisotropy is produced by different electron effective collision frequencies along and across local symmetry axis in domains of exotic ordered nuclear clusters and by complicated effects of the magnetic field. We also calculate averaged kinetic coefficients in case local domains are freely oriented. Possible applications of the obtained results and open problems are outlined.

  16. A model environment for outer zone electrons

    NASA Technical Reports Server (NTRS)

    Singley, G. W.; Vette, J. I.

    1972-01-01

    A brief morphology of outer zone electrons is given to illustrate the nature of the phenomena that we are attempting to model. This is followed by a discussion of the data processing that was done with the various data received from the experimenters before incorporating it into the data base from which this model was ultimately derived. The details of the derivation are given, and several comparisons of the final model with the various experimental measurements are presented.

  17. Electron transport in micro to nanoscale solid state networks

    NASA Astrophysics Data System (ADS)

    Fairbanks, Matthew Stetson

    This dissertation focuses on low-dimensional electron transport phenomena in devices ranging from semiconductor electron 'billiards' to semimetal atomic clusters to gold nanoparticles. In each material system, the goal of this research is to understand how carrier transport occurs when many elements act in concert. In the semiconductor electron billiards, magnetoconductance fluctuations, the result of electron quantum interference within the device, are used as a probe of electron transport through arrays of one, two, and three connected billiards. By combining two established analysis techniques, this research demonstrates a novel method for determining the quantum energy level spacing in each of the arrays. That information in turn shows the extent (and limits) of the phase-coherent electron wavefunction in each of the devices. The use of the following two material systems, the semimetal atomic clusters and the gold nanoparticles, is inspired by the electron billiard results. First, the output of the simple, rectangular electron billiards, the magnetoconductance fluctuations, is quite generally found to be fractal. This research addresses the question of what output one might expect from a device with manifestly fractal geometry by simulating the electrical response of fractal resistor networks and by outlining a method to implement such devices in fractal aggregates of semimetal atomic clusters. Second, in gold nanoparticle arrays, the number of array elements can increase by orders of magnitude over the billiard arrays, all with the potential to stay in a similar, phase-coherent transport regime. The last portion of this dissertation details the fabrication of these nanoparticle-based devices and their electrical characteristics, which exhibit strong evidence for electron transport in the Coulomb-blockade regime. A sketch for further 'off-blockade' experiments to realize magnetoconductance fluctuations, i.e. phase-coherent electron phenomena, is presented.

  18. Treating electron transport in MCNP{sup trademark}

    SciTech Connect

    Hughes, H.G.

    1996-12-31

    The transport of electrons and other charged particles is fundamentally different from that of neutrons and photons. A neutron, in aluminum slowing down from 0.5 MeV to 0.0625 MeV will have about 30 collisions; a photon will have fewer than ten. An electron with the same energy loss will undergo 10{sup 5} individual interactions. This great increase in computational complexity makes a single- collision Monte Carlo approach to electron transport unfeasible for many situations of practical interest. Considerable theoretical work has been done to develop a variety of analytic and semi-analytic multiple-scattering theories for the transport of charged particles. The theories used in the algorithms in MCNP are the Goudsmit-Saunderson theory for angular deflections, the Landau an theory of energy-loss fluctuations, and the Blunck-Leisegang enhancements of the Landau theory. In order to follow an electron through a significant energy loss, it is necessary to break the electron`s path into many steps. These steps are chosen to be long enough to encompass many collisions (so that multiple-scattering theories are valid) but short enough that the mean energy loss in any one step is small (for the approximations in the multiple-scattering theories). The energy loss and angular deflection of the electron during each step can then be sampled from probability distributions based on the appropriate multiple- scattering theories. This subsumption of the effects of many individual collisions into single steps that are sampled probabilistically constitutes the ``condensed history`` Monte Carlo method. This method is exemplified in the ETRAN series of electron/photon transport codes. The ETRAN codes are also the basis for the Integrated TIGER Series, a system of general-purpose, application-oriented electron/photon transport codes. The electron physics in MCNP is similar to that of the Integrated TIGER Series.

  19. Topological transport in Dirac electronic systems: A concise review

    NASA Astrophysics Data System (ADS)

    Song, Hua-Ding; Sheng, Dian; Wang, An-Qi; Li, Jin-Guang; Yu, Da-Peng; Liao, Zhi-Min

    2017-03-01

    Various novel physical properties have emerged in Dirac electronic systems, especially the topological characters protected by symmetry. Current studies on these systems have been greatly promoted by the intuitive concepts of Berry phase and Berry curvature, which provide precise definitions of the topological orders. In this topical review, transport properties of topological insulator (Bi2Se3), topological Dirac semimetal (Cd3As2) and topological insulator-graphene heterojunction are presented and discussed. Perspectives about transport properties of two-dimensional topological nontrivial systems, including topological edge transport, topological valley transport and topological Weyl semimetals, are provided.

  20. Conditioner for a helically transported electron beam

    SciTech Connect

    Wang, C.

    1992-05-01

    The kinetic theory is developed to investigate a conditioner for a helically imported electron beam. Linear expressions for axial velocity spread are derived. Numerical simulation is used to check the theoretical results and examine nonlinear aspects of the conditioning process. The results show that in the linear regime the action of the beam conditioner on a pulsed beam mainly depends on the phase at which the beam enters the conditioner and depends only slightly on the operating wavelength. In the nonlinear regime, however, the action of the conditioner strongly depends on the operating wavelength and only slightly upon the entrance phase. For a properly chosen operating wavelength, a little less than the electron's relativistic cyclotron wavelength, the conditioner can decrease the axial velocity spread of a pulsed beam down to less than one-third of its initial value.

  1. Monte Carlo simulations of electron transport in strongly attaching gases

    NASA Astrophysics Data System (ADS)

    Petrovic, Zoran; Miric, Jasmina; Simonovic, Ilija; Bosnjakovic, Danko; Dujko, Sasa

    2016-09-01

    Extensive loss of electrons in strongly attaching gases imposes significant difficulties in Monte Carlo simulations at low electric field strengths. In order to compensate for such losses, some kind of rescaling procedures must be used. In this work, we discuss two rescaling procedures for Monte Carlo simulations of electron transport in strongly attaching gases: (1) discrete rescaling, and (2) continuous rescaling. The discrete rescaling procedure is based on duplication of electrons randomly chosen from the remaining swarm at certain discrete time steps. The continuous rescaling procedure employs a dynamically defined fictitious ionization process with the constant collision frequency chosen to be equal to the attachment collision frequency. These procedures should not in any way modify the distribution function. Monte Carlo calculations of transport coefficients for electrons in SF6 and CF3I are performed in a wide range of electric field strengths. However, special emphasis is placed upon the analysis of transport phenomena in the limit of lower electric fields where the transport properties are strongly affected by electron attachment. Two important phenomena arise: (1) the reduction of the mean energy with increasing E/N for electrons in SF6, and (2) the occurrence of negative differential conductivity in the bulk drift velocity of electrons in both SF6 and CF3I.

  2. Introduction to special section on Colloid Transport in Subsurface Environments

    NASA Astrophysics Data System (ADS)

    Saiers, James E.; Ryan, Joseph N.

    2006-12-01

    The Water Resources Research special section on Colloid Transport in Subsurface Environments presents new knowledge that is critical to solving problems related to groundwater pollution by microbial pathogens and hazardous chemicals. This introduction to the special section surveys fourteen manuscripts that advance current understanding of the transport of biocolloids (e.g., bacteria, viruses, and protozoa), mineral colloids, and colloid-associated contaminants in the vadose zone and in groundwater. These papers present new techniques for elucidating mechanisms that govern colloid mobility, propose mathematical models appropriate for quantifying colloid and colloid-associated contaminant transport, and report pore-scale and column-scale observations requisite for evaluating these models. Together, the papers of this special section illuminate the complexity of the colloid transport problem and describe progress toward understanding this complexity.

  3. Non-equilibrium normal and critical transport of electrons in strontium-doped bismuthate cuprates

    NASA Astrophysics Data System (ADS)

    Kwang-Hua, Chu Rainer

    2014-05-01

    Critical dynamical transitional phases of electronic liquids driven by an initial electric field in a microscopic confined environment at low temperature regime could occur after we investigated by adopting the verified theory of absolute reactions. The critical temperatures related to the nearly frictionless transport of many condensed electrons might be directly relevant to the dynamical transition at low-temperature regime in amorphous materials, say (Bi2-xSrx)2CuO6, after selecting specific activation energies and activation volumes. We also address the normal-state high-temperature transport issue.

  4. Transport and Non-Invasive Position Detection of Electron Beams from Laser-Plasma Accelerators

    SciTech Connect

    Osterhoff, Jens; Sokollik, Thomas; Nakamura, Kei; Bakeman, Michael; Weingartner, R; Gonsalves, Anthony; Shiraishi, Satomi; Lin, Chen; vanTilborg, Jeroen; Geddes, Cameron; Schroeder, Carl; Esarey, Eric; Toth, Csaba; DeSantis, Stefano; Byrd, John; Gruner, F; Leemans, Wim

    2011-07-20

    The controlled imaging and transport of ultra-relativistic electrons from laser-plasma accelerators is of crucial importance to further use of these beams, e.g. in high peak-brightness light sources. We present our plans to realize beam transport with miniature permanent quadrupole magnets from the electron source through our THUNDER undulator. Simulation results demonstrate the importance of beam imaging by investigating the generated XUV-photon flux. In addition, first experimental findings of utilizing cavity-based monitors for non-invasive beam-position measurements in a noisy electromagnetic laser-plasma environment are discussed.

  5. Electronic Structure and Transport in Magnetic Multilayers

    SciTech Connect

    2008-02-18

    ORNL assisted Seagate Recording Heads Operations in the development of CIPS pin Valves for application as read sensors in hard disk drives. Personnel at ORNL were W. H. Butler and Xiaoguang Zhang. Dr. Olle Heinonen from Seagate RHO also participated. ORNL provided codes and materials parameters that were used by Seagate to model CIP GMR in their heads. The objectives were to: (1) develop a linearized Boltzmann transport code for describing CIP GMR based on realistic models of the band structure and interfaces in materials in CIP spin valves in disk drive heads; (2) calculate the materials parameters needed as inputs to the Boltzmann code; and (3) transfer the technology to Seagate Recording Heads.

  6. Evidence for global electron transportation into the jovian inner magnetosphere.

    PubMed

    Yoshioka, K; Murakami, G; Yamazaki, A; Tsuchiya, F; Kimura, T; Kagitani, M; Sakanoi, T; Uemizu, K; Kasaba, Y; Yoshikawa, I; Fujimoto, M

    2014-09-26

    Jupiter's magnetosphere is a strong particle accelerator that contains ultrarelativistic electrons in its inner part. They are thought to be accelerated by whistler-mode waves excited by anisotropic hot electrons (>10 kiloelectron volts) injected from the outer magnetosphere. However, electron transportation in the inner magnetosphere is not well understood. By analyzing the extreme ultraviolet line emission from the inner magnetosphere, we show evidence for global inward transport of flux tubes containing hot plasma. High-spectral-resolution scanning observations of the Io plasma torus in the inner magnetosphere enable us to generate radial profiles of the hot electron fraction. It gradually decreases with decreasing radial distance, despite the short collisional time scale that should thermalize them rapidly. This indicates a fast and continuous resupply of hot electrons responsible for exciting the whistler-mode waves.

  7. 76 FR 50312 - Surface Transportation Environment and Planning Cooperative Research Program (STEP)

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-08-12

    ... Federal Highway Administration Surface Transportation Environment and Planning Cooperative Research...-LU) established the Surface Transportation Environment and Planning Cooperative Research Program... research on issues related to planning, environment, and realty will be included in future...

  8. 77 FR 38709 - Surface Transportation Environment and Planning Cooperative Research Program (STEP)

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-06-28

    ... Federal Highway Administration Surface Transportation Environment and Planning Cooperative Research...-LU) established the Surface Transportation Environment and Planning Cooperative Research Program... research on issues related to planning, environment, and realty will be included in future...

  9. Unification of trap-limited electron transport in semiconducting polymers.

    PubMed

    Nicolai, H T; Kuik, M; Wetzelaer, G A H; de Boer, B; Campbell, C; Risko, C; Brédas, J L; Blom, P W M

    2012-10-01

    Electron transport in semiconducting polymers is usually inferior to hole transport, which is ascribed to charge trapping on isolated defect sites situated within the energy bandgap. However, a general understanding of the origin of these omnipresent charge traps, as well as their energetic position, distribution and concentration, is lacking. Here we investigate electron transport in a wide range of semiconducting polymers by current-voltage measurements of single-carrier devices. We observe for this materials class that electron transport is limited by traps that exhibit a gaussian energy distribution in the bandgap. Remarkably, the electron-trap distribution is identical for all polymers considered: the number of traps amounts to 3 × 10(23) traps per m(3) centred at an energy of ~3.6 eV below the vacuum level, with a typical distribution width of ~0.1 eV. This indicates that the electron traps have a common origin that, we suggest, is most likely related to hydrated oxygen complexes. A consequence of this finding is that the trap-limited electron current can be predicted for any polymer.

  10. Advanced Engineering Environments for Space Transportation System Development

    NASA Technical Reports Server (NTRS)

    Thomas, L. Dale; Smith, Charles A.; Beveridge, James

    2000-01-01

    There are significant challenges facing today's launch vehicle industry. Global competition, more complex products, geographically-distributed design teams, demands for lower cost, higher reliability and safer vehicles, and the need to incorporate the latest technologies quicker, all face the developer of a space transportation system. Within NASA, multiple technology development and demonstration projects are underway toward the objectives of safe, reliable, and affordable access to space. New information technologies offer promising opportunities to develop advanced engineering environments to meet these challenges. Significant advances in the state-of-the-art of aerospace engineering practice are envisioned in the areas of engineering design and analytical tools, cost and risk tools, collaborative engineering, and high-fidelity simulations early in the development cycle. At the Marshall Space Flight Center, work has begun on development of an advanced engineering environment specifically to support the design, modeling, and analysis of space transportation systems. This paper will give an overview of the challenges of developing space transportation systems in today's environment and subsequently discuss the advanced engineering environment and its anticipated benefits.

  11. Radiation-Hardened Electronics for Space Environments (RHESE)

    NASA Technical Reports Server (NTRS)

    Keys, Andrew S.; Adams, James H.; Patrick, Marshall C.; Johnson, Michael; Cressler, John D.

    2008-01-01

    This conference poster explores NASA's Radiation-Hardened Electronics for Space Environments project. This project aims to advance the state of the art in high performance, radiation-hardened electronics that enable the long-term, reliable operation of a spacecraft in extreme radiation and temperature of space and the lunar surface.

  12. Effect of dephasing on DNA sequencing via transverse electronic transport

    SciTech Connect

    Zwolak, Michael; Krems, Matt; Pershin, Yuriy V; Di Ventra, Massimiliano

    2009-01-01

    We study theoretically the effects of dephasing on DNA sequencing in a nanopore via transverse electronic transport. To do this, we couple classical molecular dynamics simulations with transport calculations using scattering theory. Previous studies, which did not include dephasing, have shown that by measuring the transverse current of a particular base multiple times, one can get distributions of currents for each base that are distinguishable. We introduce a dephasing parameter into transport calculations to simulate the effects of the ions and other fluctuations. These effects lower the overall magnitude of the current, but have little effect on the current distributions themselves. The results of this work further implicate that distinguishing DNA bases via transverse electronic transport has potential as a sequencing tool.

  13. Mitochondrial ROS Produced via Reverse Electron Transport Extend Animal Lifespan.

    PubMed

    Scialò, Filippo; Sriram, Ashwin; Fernández-Ayala, Daniel; Gubina, Nina; Lõhmus, Madis; Nelson, Glyn; Logan, Angela; Cooper, Helen M; Navas, Plácido; Enríquez, Jose Antonio; Murphy, Michael P; Sanz, Alberto

    2016-04-12

    Increased production of reactive oxygen species (ROS) has long been considered a cause of aging. However, recent studies have implicated ROS as essential secondary messengers. Here we show that the site of ROS production significantly contributes to their apparent dual nature. We report that ROS increase with age as mitochondrial function deteriorates. However, we also demonstrate that increasing ROS production specifically through respiratory complex I reverse electron transport extends Drosophila lifespan. Reverse electron transport rescued pathogenesis induced by severe oxidative stress, highlighting the importance of the site of ROS production in signaling. Furthermore, preventing ubiquinone reduction, through knockdown of PINK1, shortens lifespan and accelerates aging; phenotypes that are rescued by increasing reverse electron transport. These results illustrate that the source of a ROS signal is vital in determining its effects on cellular physiology and establish that manipulation of ubiquinone redox state is a valid strategy to delay aging.

  14. Mitochondrial ROS Produced via Reverse Electron Transport Extend Animal Lifespan

    PubMed Central

    Scialò, Filippo; Sriram, Ashwin; Fernández-Ayala, Daniel; Gubina, Nina; Lõhmus, Madis; Nelson, Glyn; Logan, Angela; Cooper, Helen M.; Navas, Plácido; Enríquez, Jose Antonio; Murphy, Michael P.; Sanz, Alberto

    2016-01-01

    Summary Increased production of reactive oxygen species (ROS) has long been considered a cause of aging. However, recent studies have implicated ROS as essential secondary messengers. Here we show that the site of ROS production significantly contributes to their apparent dual nature. We report that ROS increase with age as mitochondrial function deteriorates. However, we also demonstrate that increasing ROS production specifically through respiratory complex I reverse electron transport extends Drosophila lifespan. Reverse electron transport rescued pathogenesis induced by severe oxidative stress, highlighting the importance of the site of ROS production in signaling. Furthermore, preventing ubiquinone reduction, through knockdown of PINK1, shortens lifespan and accelerates aging; phenotypes that are rescued by increasing reverse electron transport. These results illustrate that the source of a ROS signal is vital in determining its effects on cellular physiology and establish that manipulation of ubiquinone redox state is a valid strategy to delay aging. PMID:27076081

  15. Best Practices Experiences: Successful Use of Electronic Learning Environments.

    ERIC Educational Resources Information Center

    de Boer, W. F.; Fisser, P. H. G.

    Two popular learning environments, TeleTOP and Blackboard, are implemented for specific educational contexts in many universities and other institutions. The goal is to increase the use of information and communication technology (ICT) in education, particularly network technology or Web-based systems. These electronic learning environments do not…

  16. Progress in Simulating Turbulent Electron Thermal Transport in NSTX

    SciTech Connect

    Guttenfelder, Walter; Kaye, S. M.; Ren, Y.; Bell, R. E.; Hammett, G. W.; LeBlanc, B. P.; Mikkelsen, D. R.; Peterson, J. L.; Nevins, W. M.; Candy, J.; Yuh, H.

    2013-07-17

    Nonlinear simulations based on multiple NSTX discharge scenarios have progressed to help differentiate unique instability mechanisms and to validate with experimental turbulence and transport data. First nonlinear gyrokinetic simulations of microtearing (MT) turbulence in a high-beta NSTX H-mode discharge predict experimental levels of electron thermal transport that are dominated by magnetic flutter and increase with collisionality, roughly consistent with energy confinement times in dimensionless collisionality scaling experiments. Electron temperature gradient (ETG) simulations predict significant electron thermal transport in some low and high beta discharges when ion scales are suppressed by E x B shear. Although the predicted transport in H-modes is insensitive to variation in collisionality (inconsistent with confinement scaling), it is sensitive to variations in other parameters, particularly density gradient stabilization. In reversed shear (RS) Lmode discharges that exhibit electron internal transport barriers, ETG transport has also been shown to be suppressed nonlinearly by strong negative magnetic shear, s<<0. In many high beta plasmas, instabilities which exhibit a stiff beta dependence characteristic of kinetic ballooning modes (KBM) are sometimes found in the core region. However, they do not have a distinct finite beta threshold, instead transitioning gradually to a trapped electron mode (TEM) as beta is reduced to zero. Nonlinear simulations of this "hybrid" TEM/KBM predict significant transport in all channels, with substantial contributions from compressional magnetic perturbations. As multiple instabilities are often unstable simultaneously in the same plasma discharge, even on the same flux surface, unique parametric dependencies are discussed which may be useful for distinguishing the different mechanisms experimentally.

  17. Coherently driven, ultrafast electron-phonon dynamics in transport junctions

    SciTech Connect

    Szekely, Joshua E.; Seideman, Tamar

    2014-07-28

    Although the vast majority of studies of transport via molecular-scale heterojunctions have been conducted in the (static) energy domain, experiments are currently beginning to apply time domain approaches to the nanoscale transport problem, combining spatial with temporal resolution. It is thus an opportune time for theory to develop models to explore both new phenomena in, and new potential applications of, time-domain, coherently driven molecular electronics. In this work, we study the interaction of a molecular phonon with an electronic wavepacket transmitted via a conductance junction within a time-domain model that treats the electron and phonon on equal footing and spans the weak to strong electron-phonon coupling strengths. We explore interference between two coherent energy pathways in the electronic subspace, thus complementing previous studies of coherent phenomena in conduction junctions, where the stationary framework was used to study interference between spatial pathways. Our model provides new insights into phase decoherence and population relaxation within the electronic subspace, which have been conventionally treated by density matrix approaches that often rely on phenomenological parameters. Although the specific case of a transport junction is explored, our results are general, applying also to other instances of coupled electron-phonon systems.

  18. Electron cross-sections and transport in liquids and biomolecules

    NASA Astrophysics Data System (ADS)

    White, Ronald; Casey, M.; Cocks, D.; Konvalov, D.; Brunger, M. J.; Garcia, G.; Petrovic, Z.; McEachran, R.; Buckman, S. J.; de Urquijo, J.

    2016-09-01

    Modelling of electron induced processes in plasma medicine and radiation damage is reliant on accurate self-consistent sets of cross-sections for electrons in tissue. These cross-sections (and associated transport theory) must accurately account not only the electron-biomolecule interactions but also for the soft-condensed nature of tissue. In this presentation, we report on recent swarm experiments for electrons in gaseous water and tetrahydrofuran using the pulsed-Townsend experiment, and the associated development of self-consistent cross-section sets that arise from them. We also report on the necessary modifications to gas-phase cross-sections required to accurately treat electron transport in liquids. These modifications involve the treatment of coherent scattering and screening of the electron interaction potential as well as the development of a new transport theory to accommodate these cross-sections. The accuracy of the ab-initio cross-sections is highlighted through comparison of theory and experiment for electrons in liquid argon and xenon.

  19. Quantum Transport in Solids: Two-Electron Processes.

    DTIC Science & Technology

    1995-07-01

    The central objective of this research program has been to study theoretically the underlying principles of quantum transport in solids. The area of...research investigated has emphasized the understanding of two electron processes in quantum transport . The problems have been treated analytically to...the extent possible through the use of dynamical localized Wannier functions. These results have been and are being incorporated in a full quantum

  20. Quantum Transport in Solids: Two-Electron Processes.

    DTIC Science & Technology

    1995-06-01

    The central objective of this research program has been to study theoretically the underlying principles of quantum transport in solids. The area of...research investigated has emphasized the understanding of two electron processes in quantum transport . The problems have been treated analytically to...the extent possible through the use of dynamical localized Wannier functions. These results have been and are being incorporated in a full quantum

  1. Collective microdynamics and noise suppression in dispersive electron beam transport

    SciTech Connect

    Gover, Avraham; Dyunin, Egor; Duchovni, Tamir; Nause, Ariel

    2011-12-15

    A general formulation is presented for deep collective interaction micro-dynamics in dispersive e-beam transport. In the regime of transversely coherent interaction, the formulation is applicable to both coherent and random temporal modulation of the electron beam. We demonstrate its use for determining the conditions for suppressing beam current noise below the classical shot-noise level by means of transport through a dispersive section with a small momentum compaction parameter.

  2. Simulation of electron transport in quantum well devices

    NASA Technical Reports Server (NTRS)

    Miller, D. R.; Gullapalli, K. K.; Reddy, V. R.; Neikirk, D. P.

    1992-01-01

    Double barrier resonant tunneling diodes (DBRTD) have received much attention as possible terahertz devices. Despite impressive experimental results, the specifics of the device physics (i.e., how the electrons propagate through the structure) are only qualitatively understood. Therefore, better transport models are warranted if this technology is to mature. In this paper, the Lattice Wigner function is used to explain the important transport issues associated with DBRTD device behavior.

  3. Transport properties of anyons in random topological environments

    NASA Astrophysics Data System (ADS)

    Zatloukal, V.; Lehman, L.; Singh, S.; Pachos, J. K.; Brennen, G. K.

    2014-10-01

    The quasi-one-dimensional transport of Abelian and non-Abelian anyons is studied in the presence of a random topological background. In particular, we consider the quantum walk of an anyon that braids around islands of randomly filled static anyons of the same type. Two distinct behaviors are identified. We analytically demonstrate that all types of Abelian anyons localize purely due to the statistical phases induced by their random anyonic environment. In contrast, we numerically show that non-Abelian Ising anyons do not localize. This is due to their entanglement with the anyonic environment, which effectively induces dephasing. Our study demonstrates that localization properties strongly depend on nonlocal topological interactions, and it provides a clear distinction in the transport properties of Abelian and non-Abelian anyons.

  4. Origin of electronic transport of lithium phthalocyanine iodine crystal

    SciTech Connect

    Koike, Noritake; Oda, Masato; Shinozuka, Yuzo

    2013-12-04

    The electronic structures of Lithium Phthalocyanine Iodine are investigated using density functional theory. Comparing the band structures of several model crystals, the metallic conductivity of highly doped LiPcI{sub x} can be explained by the band of doped iodine. These results reveal that there is a new mechanism for electronic transport of doped organic semiconductors that the dopant band plays the main role.

  5. Study of Electron Transport and Amplification in Diamond

    SciTech Connect

    Muller, Erik M.; Ben-Zvi, Ilan

    2013-03-31

    As a successful completion of this award, my group has demonstrated world-leading electron gain from diamond for use in a diamond-amplified photocathode. Also, using high-resolution photoemission measurements we were able to uncover exciting new physics of the electron emission mechanisms from hydrogen terminated diamond. Our work, through the continued support of HEP, has resulted in a greater understanding of the diamond material science, including current limits, charge transport modeling, and spatial uniformity.

  6. Electron transport in EBT in the low collision frequency limit

    SciTech Connect

    Hastings, D.E.

    1984-06-01

    A variational principle formulation is used to calculate the electron neoclassical transport coefficients in a bumpy torus for the low collisionality regime. The electron radial drift is calculated as a function of the plasma position and the poloidal electric field which is determined self-consistently. A bounce-averaged differential collision operator is used and the results are compared to previous treatments using a BGK operator.

  7. Silicon Carbide Sensors and Electronics for Harsh Environment Applications

    NASA Technical Reports Server (NTRS)

    Evans, Laura J.

    2007-01-01

    Silicon carbide (SiC) semiconductor has been studied for electronic and sensing applications in extreme environment (high temperature, extreme vibration, harsh chemical media, and high radiation) that is beyond the capability of conventional semiconductors such as silicon. This is due to its near inert chemistry, superior thermomechanical and electronic properties that include high breakdown voltage and wide bandgap. An overview of SiC sensors and electronics work ongoing at NASA Glenn Research Center (NASA GRC) will be presented. The main focus will be two technologies currently being investigated: 1) harsh environment SiC pressure transducers and 2) high temperature SiC electronics. Work highlighted will include the design, fabrication, and application of SiC sensors and electronics, with recent advancements in state-of-the-art discussed as well. These combined technologies are studied for the goal of developing advanced capabilities for measurement and control of aeropropulsion systems, as well as enhancing tools for exploration systems.

  8. Electron transport in magnetrons by a posteriori Monte Carlo simulations

    NASA Astrophysics Data System (ADS)

    Costin, C.; Minea, T. M.; Popa, G.

    2014-02-01

    Electron transport across magnetic barriers is crucial in all magnetized plasmas. It governs not only the plasma parameters in the volume, but also the fluxes of charged particles towards the electrodes and walls. It is particularly important in high-power impulse magnetron sputtering (HiPIMS) reactors, influencing the quality of the deposited thin films, since this type of discharge is characterized by an increased ionization fraction of the sputtered material. Transport coefficients of electron clouds released both from the cathode and from several locations in the discharge volume are calculated for a HiPIMS discharge with pre-ionization operated in argon at 0.67 Pa and for very short pulses (few µs) using the a posteriori Monte Carlo simulation technique. For this type of discharge electron transport is characterized by strong temporal and spatial dependence. Both drift velocity and diffusion coefficient depend on the releasing position of the electron cloud. They exhibit minimum values at the centre of the race-track for the secondary electrons released from the cathode. The diffusion coefficient of the same electrons increases from 2 to 4 times when the cathode voltage is doubled, in the first 1.5 µs of the pulse. These parameters are discussed with respect to empirical Bohm diffusion.

  9. Transportation of a microwave environment over networks and the applications

    NASA Astrophysics Data System (ADS)

    Shoji, Yozo

    2012-01-01

    The concept of the transportation of a microwave environment over networks using a digitized Radio-on-Fibre (DRoF) technique as well as the concept of in-network microwave processing, which could make the concept of "wired and wireless network virtualization" into a reality, is discussed. The new applications to a radio-on-demand service (RoD), software-defined radio-aware network (SDRAN), and microwave environments cloud are introduced. 10-Gbps Ethernet based microwave-to-network interface converter (MiNIC) are developed and the transportation of multiple digital TV broadcasting signals is demonstrated. It is shown that the MiNIC should use more than 8-bits resolution in digitization of a microwave environment when 7 channels of TV signals are included in it. The concept of remote microwave environments observation over networks is demonstrated, where the frequency channel and received signal strength indication (RSSI) of the detected digital TV broadcasting signals are remotely monitored.

  10. High Temperature Electronics for Intelligent Harsh Environment Sensors

    NASA Technical Reports Server (NTRS)

    Evans, Laura J.

    2008-01-01

    The development of intelligent instrumentation systems is of high interest in both public and private sectors. In order to obtain this ideal in extreme environments (i.e., high temperature, extreme vibration, harsh chemical media, and high radiation), both sensors and electronics must be developed concurrently in order that the entire system will survive for extended periods of time. The semiconductor silicon carbide (SiC) has been studied for electronic and sensing applications in extreme environment that is beyond the capability of conventional semiconductors such as silicon. The advantages of SiC over conventional materials include its near inert chemistry, superior thermomechanical properties in harsh environments, and electronic properties that include high breakdown voltage and wide bandgap. An overview of SiC sensors and electronics work ongoing at NASA Glenn Research Center (NASA GRC) will be presented. The main focus will be two technologies currently being investigated: 1) harsh environment SiC pressure transducers and 2) high temperature SiC electronics. Work highlighted will include the design, fabrication, and application of SiC sensors and electronics, with recent advancements in state-of-the-art discussed as well. These combined technologies are studied for the goal of developing advanced capabilities for measurement and control of aeropropulsion systems, as well as enhancing tools for exploration systems.

  11. Molecular modeling of inelastic electron transport in molecular junctions

    NASA Astrophysics Data System (ADS)

    Jiang, Jun; Kula, Mathias; Luo, Yi

    2008-09-01

    A quantum chemical approach for the modeling of inelastic electron tunneling spectroscopy of molecular junctions based on scattering theory is presented. Within a harmonic approximation, the proposed method allows us to calculate the electron-vibration coupling strength analytically, which makes it applicable to many different systems. The calculated inelastic electron transport spectra are often in very good agreement with their experimental counterparts, allowing the revelation of detailed information about molecular conformations inside the junction, molecule-metal contact structures, and intermolecular interaction that is largely inaccessible experimentally.

  12. Transport Experiments on 2D Correlated Electron Physics in Semiconductors

    SciTech Connect

    Tsui, Daniel

    2014-03-24

    This research project was designed to investigate experimentally the transport properties of the 2D electrons in Si and GaAs, two prototype semiconductors, in several new physical regimes that were previously inaccessible to experiments. The research focused on the strongly correlated electron physics in the dilute density limit, where the electron potential energy to kinetic energy ratio rs>>1, and on the fractional quantum Hall effect related physics in nuclear demagnetization refrigerator temperature range on samples with new levels of purity and controlled random disorder.

  13. ELECTRONIC AND TRANSPORT PROPERTIES OF THERMOELECTRIC Ru2Si3

    NASA Astrophysics Data System (ADS)

    Singh, David J.; Parker, David

    2013-08-01

    We report calculations of the doping and temperature dependent thermopower of Ru2Si3 based on Boltzmann transport theory and the first principles electronic structure. We find that the performance reported to date can be significantly improved by optimization of the doping level and that ultimately n-type should have higher ZT than p-type.

  14. Requirement for Coenzyme Q in Plasma Membrane Electron Transport

    NASA Astrophysics Data System (ADS)

    Sun, I. L.; Sun, E. E.; Crane, F. L.; Morre, D. J.; Lindgren, A.; Low, H.

    1992-12-01

    Coenzyme Q is required in the electron transport system of rat hepatocyte and human erythrocyte plasma membranes. Extraction of coenzyme Q from the membrane decreases NADH dehydrogenase and NADH:oxygen oxidoreductase activity. Addition of coenzyme Q to the extracted membrane restores the activity. Partial restoration of activity is also found with α-tocopherylquinone, but not with vitamin K_1. Analogs of coenzyme Q inhibit NADH dehydrogenase and oxidase activity and the inhibition is reversed by added coenzyme Q. Ferricyanide reduction by transmembrane electron transport from HeLa cells is inhibited by coenzyme Q analogs and restored with added coenzyme Q10. Reduction of external ferricyanide and diferric transferrin by HeLa cells is accompanied by proton release from the cells. Inhibition of the reduction by coenzyme Q analogs also inhibits the proton release, and coenzyme Q10 restores the proton release activity. Trans-plasma membrane electron transport stimulates growth of serum-deficient cells, and added coenzyme Q10 increases growth of HeLa (human adenocarcinoma) and BALB/3T3 (mouse fibroblast) cells. The evidence is consistent with a function for coenzyme Q in a trans-plasma membrane electron transport system which influences cell growth.

  15. Investigation of electron beam transport in a helical undulator

    SciTech Connect

    Jeong, Y.U.; Lee, B.C.; Kim, S.K.

    1995-12-31

    Lossless transport of electrons through the undulator is essential for CW operation of the FELs driven by recirculating electrostatic accelerators. We calculate the transport ratio of an electron beam in a helical undulator by using a 3-D simulation code and compare the results with the experimental results. The energy and the current of the electron beam are 400 keV and 2 A, respectively. The 3-D distribution of the magnetic field of a practical permanent-magnet helical undulator is measured and is used in the calculations. The major parameters of the undutlator are : period = 32 mm, number of periods = 20, number of periods in adiabatic region = 3.5, magnetic field strength = 1.3 kG. The transport ratio is very sensitive to the injection condition of the electron beam such as the emittance, the diameter, the divergence, etc.. The injection motion is varied in the experiments by changing the e-gun voltage or the field strength of the focusing magnet located at the entrance of the undulator. It is confirmed experimentally and with simulations that most of the beam loss occurs at the adiabatic region of the undulator regardless of the length of the adiabatic region The effect of axial guiding magnetic field on the beam finish is investigated. According to the simulations, the increase of the strength of axial magnetic field from 0 to 1 kG results in the increase of the transport ratio from 15 % to 95%.

  16. Electronic transport in gadolinium atomic-size contacts

    NASA Astrophysics Data System (ADS)

    Olivera, B.; Salgado, C.; Lado, J. L.; Karimi, A.; Henkel, V.; Scheer, E.; Fernández-Rossier, J.; Palacios, J. J.; Untiedt, C.

    2017-02-01

    We report on the fabrication, transport measurements, and density functional theory (DFT) calculations of atomic-size contacts made of gadolinium (Gd). Gd is known to have local moments mainly associated with f electrons. These coexist with itinerant s and d bands that account for its metallic character. Here we explore whether and how the local moments influence electronic transport properties at the atomic scale. Using both scanning tunneling microscope and lithographic mechanically controllable break junction techniques under cryogenic conditions, we study the conductance of Gd when only few atoms form the junction between bulk electrodes made of the very same material. Thousands of measurements show that Gd has an average lowest conductance, attributed to single-atom contact, below 2/e2 h . Our DFT calculations for monostrand chains anticipate that the f bands are fully spin polarized and insulating and that the conduction may be dominated by s , p , and d bands. We also analyze the electronic transport for model nanocontacts using the nonequilibrium Green's function formalism in combination with DFT. We obtain an overall good agreement with the experimental results for zero bias and show that the contribution to the electronic transport from the f channels is negligible and that from the d channels is marginal.

  17. Waiting time distribution for electron transport in a molecular junction with electron-vibration interaction

    NASA Astrophysics Data System (ADS)

    Kosov, Daniel S.

    2017-02-01

    On the elementary level, electronic current consists of individual electron tunnelling events that are separated by random time intervals. The waiting time distribution is a probability to observe the electron transfer in the detector electrode at time t +τ given that an electron was detected in the same electrode at an earlier time t. We study waiting time distribution for quantum transport in a vibrating molecular junction. By treating the electron-vibration interaction exactly and molecule-electrode coupling perturbatively, we obtain the master equation and compute the distribution of waiting times for electron transport. The details of waiting time distributions are used to elucidate microscopic mechanism of electron transport and the role of electron-vibration interactions. We find that as nonequilibrium develops in the molecular junction, the skewness and dispersion of the waiting time distribution experience stepwise drops with the increase of the electric current. These steps are associated with the excitations of vibrational states by tunnelling electrons. In the strong electron-vibration coupling regime, the dispersion decrease dominates over all other changes in the waiting time distribution as the molecular junction departs far away from the equilibrium.

  18. Energy-filtered Electron Transport Structures for Low-power Low-noise 2-D Electronics

    PubMed Central

    Pan, Xuan; Qiu, Wanzhi; Skafidas, Efstratios

    2016-01-01

    In addition to cryogenic techniques, energy filtering has the potential to achieve high-performance low-noise 2-D electronic systems. Assemblies based on graphene quantum dots (GQDs) have been demonstrated to exhibit interesting transport properties, including resonant tunnelling. In this paper, we investigate GQDs based structures with the goal of producing energy filters for next generation lower-power lower-noise 2-D electronic systems. We evaluate the electron transport properties of the proposed GQD device structures to demonstrate electron energy filtering and the ability to control the position and magnitude of the energy passband by appropriate device dimensioning. We also show that the signal-to-thermal noise ratio performance of the proposed nanoscale device can be modified according to device geometry. The tunability of two-dimensional GQD structures indicates a promising route for the design of electron energy filters to produce low-power and low-noise electronics. PMID:27796343

  19. Energy-filtered Electron Transport Structures for Low-power Low-noise 2-D Electronics.

    PubMed

    Pan, Xuan; Qiu, Wanzhi; Skafidas, Efstratios

    2016-10-31

    In addition to cryogenic techniques, energy filtering has the potential to achieve high-performance low-noise 2-D electronic systems. Assemblies based on graphene quantum dots (GQDs) have been demonstrated to exhibit interesting transport properties, including resonant tunnelling. In this paper, we investigate GQDs based structures with the goal of producing energy filters for next generation lower-power lower-noise 2-D electronic systems. We evaluate the electron transport properties of the proposed GQD device structures to demonstrate electron energy filtering and the ability to control the position and magnitude of the energy passband by appropriate device dimensioning. We also show that the signal-to-thermal noise ratio performance of the proposed nanoscale device can be modified according to device geometry. The tunability of two-dimensional GQD structures indicates a promising route for the design of electron energy filters to produce low-power and low-noise electronics.

  20. Energy-filtered Electron Transport Structures for Low-power Low-noise 2-D Electronics

    NASA Astrophysics Data System (ADS)

    Pan, Xuan; Qiu, Wanzhi; Skafidas, Efstratios

    2016-10-01

    In addition to cryogenic techniques, energy filtering has the potential to achieve high-performance low-noise 2-D electronic systems. Assemblies based on graphene quantum dots (GQDs) have been demonstrated to exhibit interesting transport properties, including resonant tunnelling. In this paper, we investigate GQDs based structures with the goal of producing energy filters for next generation lower-power lower-noise 2-D electronic systems. We evaluate the electron transport properties of the proposed GQD device structures to demonstrate electron energy filtering and the ability to control the position and magnitude of the energy passband by appropriate device dimensioning. We also show that the signal-to-thermal noise ratio performance of the proposed nanoscale device can be modified according to device geometry. The tunability of two-dimensional GQD structures indicates a promising route for the design of electron energy filters to produce low-power and low-noise electronics.

  1. Crystallization of germanium-carbon alloys -- Structure and electronic transport

    SciTech Connect

    John, T.M.; Blaesing, J.; Veit, P.; Druesedau, T.

    1997-07-01

    Amorphous Ge{sub 1{minus}x}C{sub x} alloys were deposited by rf-magnetron sputtering from a germanium target in methane-argon atmosphere. Structural investigations were performed by means of wide and small angle X-ray scattering, X-ray reflectometry and cross-sectional transmission electron microscopy. The electronic transport properties were characterized using Hall-measurements and temperature depended conductivity. The results of X-ray techniques together with the electron microscopy clearly prove the existence of a segregation of the electronic conductivity in the as-prepared films follows the Mott' T{sup {minus}1/4} law, indicating transport by a hopping process. After annealing at 870 K, samples with x {le} 0.4 show crystallization of the Ge-clusters with a crystallite size being a function of x. After Ge-crystallization, the conductivity increases by 4 to 5 orders of magnitude. Above room temperature, electronic transport is determined by a thermally activated process. For lower temperatures, the {sigma}(T) curves show a behavior which is determined by the crystallite size and the free carrier concentration, both depending on the carbon content.

  2. Stopping and transport of fast electrons in superdense matter

    SciTech Connect

    Okabayashi, A.; Habara, H.; Yabuuchi, T.; Iwawaki, T.; Tanaka, K. A.

    2013-08-15

    Studied is the stopping and transport of relativistic fast electrons in the vicinity of compressed dense plasma core relevant to fast ignition. Electromagnetic cascade Monte-Carlo is coupled to 2D-PIC simulation. The 2D PIC simulates input electron energy spectrum and angular dependence. The electron energy distributions after passing through the plasma core are calculated at different viewing angles, which well agree with the experiment below several MeV energy range. The implications of calculated results as to collisional damping on several MeV electrons are discussed with the theory based on the stopping power model. The spatial distribution of plasma temperature is also estimated via deposited energy by fast electrons, showing the strong heating at the core surface.

  3. Electron transport mechanisms in polymer-carbon sphere composites

    NASA Astrophysics Data System (ADS)

    Nieves, Cesar A.; Ramos, Idalia; Pinto, Nicholas J.; Zimbovskaya, Natalya A.

    2016-07-01

    A set of uniform carbon microspheres (CSs) whose diameters have the order of 0.125 μm to 10 μm was prepared from aqueous sucrose solution by means of hydrothermal carbonization of sugar molecules. A pressed pellet was composed by mixing CSs with polyethylene oxide (PEO). Electrical characterization of the pellet was carried out showing Ohmic current-voltage characteristics and temperature-dependent conductivity in the range of 80 K electron transport. It was shown that thermally induced electron tunneling between adjacent spheres may take on an important part in the electron transport through the CS/PEO composites.

  4. Electron Beam Freeform Fabrication in the Space Environment

    NASA Technical Reports Server (NTRS)

    Taminger, Karen M.; Hafley, Robert A.

    2007-01-01

    This viewgraph presentation describes the effect of microgravity on the fabrication of electron beam freeform (EBF) in aerospace environments. The contents include: 1) Electron Beam Freeform Fabrication (EBF3) Process Description; 2) Portable Electron Beam Freeform Fabrication System at NASA LaRC; 3) Electron Beam Freeform Fabrication in the Space Environment; 4) Effect of Gravity on Surface Tension; 5) Effect of Deposit Height on Cooling Path; 6) Microgravity Testing Aboard JSC's C-9; 7) Typical Test Flight Plates; 8) Direction and Height Trials for Process Control; 9) Effect of Wire Entry Direction into Molten Pool; 10) Microstructure of Single Layer EBF Deposits; 11) 0-g Deposit with Incorrect Standoff Distance; 12) Successful Demonstration of EBF in 0-g; and 13) Conclusion.

  5. Ultrafast electron transport in graphene and magnetic nanostructures

    NASA Astrophysics Data System (ADS)

    Turchinovich, Dmitry

    2016-03-01

    Ultrafast terahertz spectroscopy is an ideal tool for observation of dynamics of charge, lattice and spin in solids on the most elementary timescale: in the regime ωτ ~ 1, where ω is the electromagnetic wave oscillation frequency, and τ is the characteristic timescale at which the fundamental phenomena in the three subsystems comprising the solid occur. In this paper two case studies will be discussed. (i) Ultrafast electron transport in graphene. We will show, that the free-carrier conductivity of graphene in arbitrary ultrafast, (sub-)picosecond electric fields is defined by the thermodynamic balance maintained within the electronic structure of graphene acting as thermalized electron gas. Within this simple thermodynamic picture, the electron gas quasi-instantaneously increases its temperature by absorbing the energy of driving ultrafast electric field, and at the same time cools down via a time-retarded, few picosecond-long process of phonon emission. The asymmetry in electron heating and cooling dynamics leads to heat accumulation in the electron population of graphene, concomitantly lowering the chemical potential for hotter electrons, and thereby reducing the intraband conductivity of graphene - an effect crucially important for understanding of ultrafast graphene transistors and photodetectors. (ii) We will also discuss the fundamental observation of spin-controlled electron conduction of Fermilevel electrons in ferromagnetic metals, and will directly quantify the Mott picture of conduction in ferromagnets - the effect directly employed in modern magnetic sensor technologies such as giant magnetoresistance.

  6. Built Environment Influences on Healthy Transportation Choices: Bicycling versus Driving

    PubMed Central

    Brauer, Michael; Setton, Eleanor M.; Teschke, Kay

    2010-01-01

    A growing body of evidence links the built environment to physical activity levels, health outcomes, and transportation behaviors. However, little of this research has focused on cycling, a sustainable transportation option with great potential for growth in North America. This study examines associations between decisions to bicycle (versus drive) and the built environment, with explicit consideration of three different spatial zones that may be relevant in travel behavior: trip origins, trip destinations, and along the route between. We analyzed 3,280 utilitarian bicycle and car trips in Metro Vancouver, Canada made by 1,902 adults, including both current and potential cyclists. Objective measures were developed for built environment characteristics related to the physical environment, land use patterns, the road network, and bicycle-specific facilities. Multilevel logistic regression was used to model the likelihood that a trip was made by bicycle, adjusting for trip distance and personal demographics. Separate models were constructed for each spatial zone, and a global model examined the relative influence of the three zones. In total, 31% (1,023 out of 3,280) of trips were made by bicycle. Increased odds of bicycling were associated with less hilliness; higher intersection density; less highways and arterials; presence of bicycle signage, traffic calming, and cyclist-activated traffic lights; more neighborhood commercial, educational, and industrial land uses; greater land use mix; and higher population density. Different factors were important within each spatial zone. Overall, the characteristics of routes were more influential than origin or destination characteristics. These findings indicate that the built environment has a significant influence on healthy travel decisions, and spatial context is important. Future research should explicitly consider relevant spatial zones when investigating the relationship between physical activity and urban form. PMID

  7. Built environment influences on healthy transportation choices: bicycling versus driving.

    PubMed

    Winters, Meghan; Brauer, Michael; Setton, Eleanor M; Teschke, Kay

    2010-12-01

    A growing body of evidence links the built environment to physical activity levels, health outcomes, and transportation behaviors. However, little of this research has focused on cycling, a sustainable transportation option with great potential for growth in North America. This study examines associations between decisions to bicycle (versus drive) and the built environment, with explicit consideration of three different spatial zones that may be relevant in travel behavior: trip origins, trip destinations, and along the route between. We analyzed 3,280 utilitarian bicycle and car trips in Metro Vancouver, Canada made by 1,902 adults, including both current and potential cyclists. Objective measures were developed for built environment characteristics related to the physical environment, land use patterns, the road network, and bicycle-specific facilities. Multilevel logistic regression was used to model the likelihood that a trip was made by bicycle, adjusting for trip distance and personal demographics. Separate models were constructed for each spatial zone, and a global model examined the relative influence of the three zones. In total, 31% (1,023 out of 3,280) of trips were made by bicycle. Increased odds of bicycling were associated with less hilliness; higher intersection density; less highways and arterials; presence of bicycle signage, traffic calming, and cyclist-activated traffic lights; more neighborhood commercial, educational, and industrial land uses; greater land use mix; and higher population density. Different factors were important within each spatial zone. Overall, the characteristics of routes were more influential than origin or destination characteristics. These findings indicate that the built environment has a significant influence on healthy travel decisions, and spatial context is important. Future research should explicitly consider relevant spatial zones when investigating the relationship between physical activity and urban form.

  8. Vibronic coupling effect on the electron transport through molecules

    NASA Astrophysics Data System (ADS)

    Tsukada, Masaru; Mitsutake, Kunihiro

    2007-03-01

    Electron transport through molecular bridges or molecular layers connected to nano-electrodes is determined by the combination of coherent and dissipative processes, controlled by the electron-vibron coupling, transfer integrals between the molecular orbitals, applied electric field and temperature. We propose a novel theoretical approach, which combines ab initio molecular orbital method with analytical many-boson model. As a case study, the long chain model of the thiophene oligomer is solved by a variation approach. Mixed states of moderately extended molecular orbital states mediated and localised by dress of vibron cloud are found as eigen-states. All the excited states accompanied by multiple quanta of vibration can be solved, and the overall carrier transport properties including the conductance, mobility, dissipation spectra are analyzed by solving the master equation with the transition rates estimated by the golden rule. We clarify obtained in a uniform systematic way, how the transport mode changes from a dominantly coherent transport to the dissipative hopping transport.

  9. Current Issues in Electron and Positron Transport Theory

    NASA Astrophysics Data System (ADS)

    Robson, Robert

    2007-10-01

    In this paper we review the current status of transport theory for low energy electrons or positrons in gases, in the context of both kinetic theory and fluid modelling. In particular, we focus on the following issues: (i) Muliterm vs two-term representation of the velocity distribution function in solution of Boltzmann's equation; (ii) the effect of non-conservative collisions (attachment, ionization, positron annihilation) on transport properties; (iii) the enduring electron- hydrogen vibrational cross section controversy and possible implications for the Boltzmann equation itself; (iv) closure of the fluid equations and the heat flux ansatz; and (v) correct use of swarm transport coefficients in fluid modelling of low temperature plasmas. Both hydrodynamic and non-hydrodynamic examples will be given, with attention focussed on the Franck-Hertz experiment, particularly the ``window'' of fields in which oscillations of transport properties are produced, and the way in which electric and magnetic fields combine to affect transport properties. In collaboration with co-authors Z. LJ. Petrovi'c, Institute of Physics Belgrade, and R.D. White, James Cook University.

  10. Theoretical descriptions of electron transport through single molecules: Developing design tools for molecular electronic devices

    NASA Astrophysics Data System (ADS)

    Carroll, Natalie R.

    There are vast numbers of organic compounds that could be considered for use in molecular electronics. Hence there is a need for efficient and economical screening tools. Here we develop theoretical methods to describe electron transport through individual molecules, the ultimate goal of which is to establish design tools for molecular electronic devices. To successfully screen a compound for its use as a device component requires a proper representation of the quantum mechanics of electron transmission. In this work we report the development of tools for the description of electron transmission that are: Charge self-consistent, valid in the presence of a finite applied potential field and (in some cases) explicitly time-dependent. In addition, the tools can be extended to any molecular system, including biosystems, because they are free of restrictive parameterizations. Two approaches are explored: (1) correlation of substituent parameter values (sigma), (commonly found in organic chemistry textbooks) to properties associated with electron transport, (2) explicit tracking of the time evolution of the wave function of a nonstationary electron. In (1) we demonstrate that the a correlate strongly with features of the charge migration process, establishing them as useful indicators of electronic properties. In (2) we employ a time-dependent description of electron transport through molecular junctions. To date, the great majority of theoretical treatments of electron transport in molecular junctions have been of the time-independent variety. Time dependence, however, is critical to such properties as switching speeds in binary computer components and alternating current conductance, so we explored methods based on time-dependent quantum mechanics. A molecular junction is modeled as a single molecule sandwiched between two clusters of close-packed metal atoms or other donor and acceptor groups. The time dependence of electron transport is investigated by initially

  11. Transport of the plasma sheet electrons to the geostationary distances

    NASA Astrophysics Data System (ADS)

    Ganushkina, N. Y.; Amariutei, O. A.; Shprits, Y.; Liemohn, M. W.

    2012-12-01

    The transport and acceleration of low energy electrons (10-250 keV) from the plasma sheet to the geostationary orbit were investigated. Two moderate storm events, which occurred on November 6-7, 1997 and June 12-14, 2005, were modeled using the Inner Magnetosphere Particle Transport and Acceleration model (IMPTAM) with the boundary set at 10 RE in the plasma sheet. The output of the IMPTAM model was compared to the observed electron fluxes in four energy ranges measured onboard the LANL spacecraft by the SOPA instrument. It was found that the large-scale convection in combination with substorm-associated impulsive fields are the drivers of the transport of plasma sheet electrons from 10 RE to geostationary orbit at 6.6 RE during storm times. The addition of radial diffusion had no significant influence on the modeled electron fluxes. At the same time, comparison between the modeled electron fluxes and observed ones showed two orders of difference most likely due to inaccuracy of electron boundary conditions and omission of the important loss processes due to wave-particle interactions. This did not allow us to accuractly reproduce the dynamics of 150-225 keV electron fluxes. The choice of the large-scale convection electric field model used in simulations did not significantly influence on the modeled electron fluxes, since there is not much difference between the equipotential contours given by the Volland-Stern and Boyle et al. [1997] models at the distances from 10 to 6.6 RE in the plasma sheet. Using the TS05 model for the background magnetic field instead of the T96 model resulted in larger deviations of the modeled electron fluxes from the observed ones due to specific features of the TS05 model. The increase in the modeled electron fluxes can be as large as three orders of magnitude when substorm-associated electromagnetic fields were taken into account. The obtained model distribution of low energy electron fluxes can be used as an input to the radiation

  12. Transport of the plasma sheet electrons to the geostationary distances

    NASA Astrophysics Data System (ADS)

    Ganushkina, N. Y.; Amariutei, O. A.; Shprits, Y. Y.; Liemohn, M. W.

    2013-01-01

    Abstract<p label="1">The <span class="hlt">transport</span> and acceleration of low-energy <span class="hlt">electrons</span> (50-250 keV) from the plasma sheet to the geostationary orbit were investigated. Two moderate storm events, which occurred on 6-7 November 1997 and 12-14 June 2005, were modeled using the Inner Magnetosphere Particle <span class="hlt">Transport</span> and Acceleration model (IMPTAM) with the boundary set at 10 RE in the plasma sheet. The output of the IMPTAM was compared to the observed <span class="hlt">electron</span> fluxes in four energy ranges (50-225 keV) measured by the Synchronous Orbit Particle Analyzer instrument onboard the Los Alamos National Laboratory spacecraft. It was found that the large-scale convection in combination with substorm-associated impulsive fields is the drivers of the <span class="hlt">transport</span> of plasma sheet <span class="hlt">electrons</span> from 10 RE to geostationary orbit at 6.6 RE during storm times. The addition of radial diffusion had no significant influence on the modeled <span class="hlt">electron</span> fluxes. At the same time, the modeled <span class="hlt">electron</span> fluxes are one (two) order(s) smaller than the observed ones for 50-150 keV (150-225 keV) <span class="hlt">electrons</span>, respectively, most likely due to inaccuracy of <span class="hlt">electron</span> boundary conditions. The loss processes due to wave-particle interactions were not considered. The choice of the large-scale convection electric field model used in simulations did not have a significant influence on the modeled <span class="hlt">electron</span> fluxes, since there is not much difference between the equipotential contours given by the Volland-Stern and the Boyle et al. (1997) models at distances from 10 to 6.6 RE in the plasma sheet. Using the TS05 model for the background magnetic field instead of the T96 model resulted in larger deviations of the modeled <span class="hlt">electron</span> fluxes from the observed ones due to specific features of the TS05 model. The increase in the modeled <span class="hlt">electron</span> fluxes can be as large as two orders of magnitude when substorm-associated electromagnetic fields were taken into account. The obtained model distribution of low-energy <span class="hlt">electron</span></p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/1096488','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/1096488"><span id="translatedtitle">LDRD project 151362 : low energy <span class="hlt">electron</span>-photon <span class="hlt">transport</span>.</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Kensek, Ronald Patrick; Hjalmarson, Harold Paul; Magyar, Rudolph J.; Bondi, Robert James; Crawford, Martin James</p> <p>2013-09-01</p> <p>At sufficiently high energies, the wavelengths of <span class="hlt">electrons</span> and photons are short enough to only interact with one atom at time, leading to the popular %E2%80%9Cindependent-atom approximation%E2%80%9D. We attempted to incorporate atomic structure in the generation of cross sections (which embody the modeled physics) to improve <span class="hlt">transport</span> at lower energies. We document our successes and failures. This was a three-year LDRD project. The core team consisted of a radiation-<span class="hlt">transport</span> expert, a solid-state physicist, and two DFT experts.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19940000063&hterms=learning+environments&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D50%26Ntt%3Dlearning%2Benvironments','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19940000063&hterms=learning+environments&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D50%26Ntt%3Dlearning%2Benvironments"><span id="translatedtitle"><span class="hlt">Transportable</span> Applications <span class="hlt">Environment</span> Plus, Version 5.1</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p></p> <p>1994-01-01</p> <p><span class="hlt">Transportable</span> Applications <span class="hlt">Environment</span> Plus (TAE+) computer program providing integrated, portable programming <span class="hlt">environment</span> for developing and running application programs based on interactive windows, text, and graphical objects. Enables both programmers and nonprogrammers to construct own custom application interfaces easily and to move interfaces and application programs to different computers. Used to define corporate user interface, with noticeable improvements in application developer's and end user's learning curves. Main components are; WorkBench, What You See Is What You Get (WYSIWYG) software tool for design and layout of user interface; and WPT (Window Programming Tools) Package, set of callable subroutines controlling user interface of application program. WorkBench and WPT's written in C++, and remaining code written in C.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016Nanot..27m5302S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016Nanot..27m5302S"><span id="translatedtitle">Geometric effects in the <span class="hlt">electronic</span> <span class="hlt">transport</span> of deformed nanotubes</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Santos, Fernando; Fumeron, Sébastien; Berche, Bertrand; Moraes, Fernando</p> <p>2016-04-01</p> <p>Quasi-two-dimensional systems may exibit curvature, which adds three-dimensional influence to their internal properties. As shown by da Costa (1981 Phys. Rev. A 23 1982-7), charged particles moving on a curved surface experience a curvature-dependent potential which greatly influence their dynamics. In this paper, we study the <span class="hlt">electronic</span> ballistic <span class="hlt">transport</span> in deformed nanotubes. The one-<span class="hlt">electron</span> Schrödinger equation with open boundary conditions is solved numerically with a flexible MAPLE code made available as supplementary data. We find that the curvature of the deformations indeed has strong effects on the <span class="hlt">electron</span> dynamics, suggesting its use in the design of nanotube-based <span class="hlt">electronic</span> devices.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/22051363','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/22051363"><span id="translatedtitle">Spatially resolved study of primary <span class="hlt">electron</span> <span class="hlt">transport</span> in magnetic cusps</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Hubble, Aimee A.; Foster, John E.</p> <p>2012-01-15</p> <p>Spatially resolved primary <span class="hlt">electron</span> current density profiles were measured using a planar Langmuir probe in the region above a magnetic cusp in a small ion thruster discharge chamber. The probe current maps obtained were used to study the <span class="hlt">electron</span> collection mechanics in the cusp region in the limit of zero gas flow and no plasma production, and they allowed for the visualization of primary <span class="hlt">electron</span> <span class="hlt">transport</span> through the cusp. Attenuation coefficients and loss widths were calculated as a function of probe distance above the anode at various operating conditions. Finally, the collection mechanics between two magnetic cusps were studied and compared. It was found that primary <span class="hlt">electron</span> collection was dominated by the upstream magnet ring.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/3847','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/3847"><span id="translatedtitle">The macro response Monte Carlo method for <span class="hlt">electron</span> <span class="hlt">transport</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Svatos, M M</p> <p>1998-09-01</p> <p>The main goal of this thesis was to prove the feasibility of basing <span class="hlt">electron</span> depth dose calculations in a phantom on first-principles single scatter physics, in an amount of time that is equal to or better than current <span class="hlt">electron</span> Monte Carlo methods. The Macro Response Monte Carlo (MRMC) method achieves run times that are on the order of conventional <span class="hlt">electron</span> <span class="hlt">transport</span> methods such as condensed history, with the potential to be much faster. This is possible because MRMC is a Local-to-Global method, meaning the problem is broken down into two separate <span class="hlt">transport</span> calculations. The first stage is a local, in this case, single scatter calculation, which generates probability distribution functions (PDFs) to describe the <span class="hlt">electron</span>'s energy, position and trajectory after leaving the local geometry, a small sphere or "kugel" A number of local kugel calculations were run for calcium and carbon, creating a library of kugel data sets over a range of incident energies (0.25 MeV - 8 MeV) and sizes (0.025 cm to 0.1 cm in radius). The second <span class="hlt">transport</span> stage is a global calculation, where steps that conform to the size of the kugels in the library are taken through the global geometry. For each step, the appropriate PDFs from the MRMC library are sampled to determine the <span class="hlt">electron</span>'s new energy, position and trajectory. The <span class="hlt">electron</span> is immediately advanced to the end of the step and then chooses another kugel to sample, which continues until <span class="hlt">transport</span> is completed. The MRMC global stepping code was benchmarked as a series of subroutines inside of the Peregrine Monte Carlo code. It was compared to Peregrine's class II condensed history <span class="hlt">electron</span> <span class="hlt">transport</span> package, EGS4, and MCNP for depth dose in simple phantoms having density inhomogeneities. Since the kugels completed in the library were of relatively small size, the zoning of the phantoms was scaled down from a clinical size, so that the energy deposition algorithms for spreading dose across 5-10 zones per kugel could be tested. Most</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://eric.ed.gov/?q=digital+AND+electronics&pg=7&id=EJ989538','ERIC'); return false;" href="http://eric.ed.gov/?q=digital+AND+electronics&pg=7&id=EJ989538"><span id="translatedtitle">Expression and Association Rights of School Employees in <span class="hlt">Electronic</span> <span class="hlt">Environments</span></span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Bathon, Justin M.</p> <p>2012-01-01</p> <p>Many of the recent legal decisions regarding public employee expression, particularly in <span class="hlt">electronic</span> <span class="hlt">environments</span>, run counter to the culture being facilitated by the Internet. This article uses a legal analysis to examine recent decisions and then considers those legal positions within the context of digital expression. (Contains 2 notes.)</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/503467','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/503467"><span id="translatedtitle">Fabrication and <span class="hlt">electronic</span> <span class="hlt">transport</span> studies of single nanocrystal systems</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Klein, David Louis</p> <p>1997-05-01</p> <p>Semiconductor and metallic nanocrystals exhibit interesting <span class="hlt">electronic</span> <span class="hlt">transport</span> behavior as a result of electrostatic and quantum mechanical confinement effects. These effects can be studied to learn about the nature of <span class="hlt">electronic</span> states in these systems. This thesis describes several techniques for the <span class="hlt">electronic</span> study of nanocrystals. The primary focus is the development of novel methods to attach leads to prefabricated nanocrystals. This is because, while nanocrystals can be readily synthesized from a variety of materials with excellent size control, means to make electrical contact to these nanocrystals are limited. The first approach that will be described uses scanning probe microscopy to first image and then electrically probe surfaces. It is found that <span class="hlt">electronic</span> investigations of nanocrystals by this technique are complicated by tip-sample interactions and environmental factors such as salvation and capillary forces. Next, an atomic force microscope technique for the catalytic patterning of the surface of a self assembled monolayer is described. In principle, this nano-fabrication technique can be used to create <span class="hlt">electronic</span> devices which are based upon complex arrangements of nanocrystals. Finally, the fabrication and electrical characterization of a nanocrystal-based single <span class="hlt">electron</span> transistor is presented. This device is fabricated using a hybrid scheme which combines <span class="hlt">electron</span> beam lithography and wet chemistry to bind single nanocrystals in tunneling contact between closely spaced metallic leads. In these devices, both Au and CdSe nanocrystals show Coulomb blockade effects with characteristic energies of several tens of meV. Additional structure is seen the <span class="hlt">transport</span> behavior of CdSe nanocrystals as a result of its <span class="hlt">electronic</span> structure.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011PhRvB..83x1404R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011PhRvB..83x1404R"><span id="translatedtitle">Single-<span class="hlt">electron</span> heat diode: Asymmetric heat <span class="hlt">transport</span> between <span class="hlt">electronic</span> reservoirs through Coulomb islands</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ruokola, Tomi; Ojanen, Teemu</p> <p>2011-06-01</p> <p>We introduce a functional nanoscale device, a single-<span class="hlt">electron</span> heat diode, consisting of two quantum dots or metallic islands coupled to <span class="hlt">electronic</span> reservoirs by tunnel contacts. <span class="hlt">Electron</span> <span class="hlt">transport</span> through the system is forbidden but the capacitive coupling between the two dots allows <span class="hlt">electronic</span> fluctuations to transmit heat between the reservoirs. When the reservoir temperatures are biased in the forward direction, heat flow is enabled by a four-step sequential tunneling cycle, while in the reverse-biased configuration this process is suppressed due to Coulomb blockade effects. In an optimal setup the leakage heat current in the reverse direction is only a few percent of the forward current.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_8");'>8</a></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li class="active"><span>10</span></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_10 --> <div id="page_11" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li class="active"><span>11</span></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="201"> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/20860240','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/20860240"><span id="translatedtitle">Nonlocal <span class="hlt">electron</span> <span class="hlt">transport</span> in magnetized plasmas with arbitrary atomic number</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Bennaceur-Doumaz, D.; Bendib, A.</p> <p>2006-09-15</p> <p>The numerical solution of the steady-state <span class="hlt">electron</span> Fokker-Planck equation perturbed with respect to a global equilibrium is presented in magnetized plasmas with arbitrary atomic number Z. The magnetic field is assumed to be constant and the <span class="hlt">electron-electron</span> collisions are described by the Landau collision operator. The solution is derived in the Fourier space and in the framework of the diffusive approximation which captures the spatial nonlocal effects. The <span class="hlt">transport</span> coefficients are deduced and used to close a complete set of nonlocal <span class="hlt">electron</span> fluid equations. This work improves the results of A. Bendib et al. [Phys. Plasmas 9, 1555 (2002)] and of A. V. Brantov et al. [Phys. Plasmas 10, 4633 (2003)] restricted to the local and nonlocal high-Z plasma approximations, respectively. The influence of the magnetic field on the nonlocal effects is discussed. We propose also accurate numerical fits of the relevant <span class="hlt">transport</span> coefficients with respect to the collisionality parameter {lambda}{sub ei}/L and the atomic number Z, where L is the typical scale length and {lambda}{sub ei} is the <span class="hlt">electron</span>-ion mean-free-path.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012ApPhL.101n1603A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012ApPhL.101n1603A"><span id="translatedtitle"><span class="hlt">Electron</span> <span class="hlt">transporting</span> water-gated thin film transistors</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Al Naim, Abdullah; Grell, Martin</p> <p>2012-10-01</p> <p>We demonstrate an <span class="hlt">electron-transporting</span> water-gated thin film transistor, using thermally converted precursor-route zinc-oxide (ZnO) intrinsic semiconductors with hexamethyldisilazene (HMDS) hydrophobic surface modification. Water gated HMDS-ZnO thin film transistors (TFT) display low threshold and high <span class="hlt">electron</span> mobility. ZnO films constitute an attractive alternative to organic semiconductors for TFT transducers in sensor applications for waterborne analytes. Despite the use of an electrolyte as gate medium, the gate geometry (shape of gate electrode and distance between gate electrode and TFT channel) is relevant for optimum performance of water-gated TFTs.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016PhRvB..94l5118W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016PhRvB..94l5118W"><span id="translatedtitle">Interlayer <span class="hlt">electronic</span> <span class="hlt">transport</span> in CaMnBi2 antiferromagnet</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Wang, Aifeng; Graf, D.; Wu, Lijun; Wang, Kefeng; Bozin, E.; Zhu, Yimei; Petrovic, C.</p> <p>2016-09-01</p> <p>We report interlayer <span class="hlt">electronic</span> <span class="hlt">transport</span> in CaMnBi2 single crystals. Quantum oscillations and angular magnetoresistance suggest coherent <span class="hlt">electronic</span> conduction and valley polarized conduction of Dirac states. The small cyclotron mass, high mobility of carriers, and nontrivial Berry's phase are consistent with the presence of Dirac fermions on the side wall of the warped cylindrical Fermi surface. Similarly to SrMnBi2, which features an anisotropic Dirac cone, our results suggest that magnetic-field-induced changes in interlayer conduction are also present in layered bismuth-based materials with a zero-energy line in momentum space created by the staggered alkaline earth atoms.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/pages/biblio/1345748-interlayer-electronic-transport-camnbi2-antiferromagnet','SCIGOV-DOEP'); return false;" href="https://www.osti.gov/pages/biblio/1345748-interlayer-electronic-transport-camnbi2-antiferromagnet"><span id="translatedtitle">Interlayer <span class="hlt">electronic</span> <span class="hlt">transport</span> in CaMnBi2 antiferromagnet</span></a></p> <p><a target="_blank" href="http://www.osti.gov/pages">DOE PAGES</a></p> <p>Wang, Aifeng; Graf, D.; Wu, Lijun; ...</p> <p>2016-09-12</p> <p>Here, we report interlayer <span class="hlt">electronic</span> <span class="hlt">transport</span> in CaMnBi2 single crystals. Quantum oscillations and angular magnetoresistance suggest coherent <span class="hlt">electronic</span> conduction and valley polarized conduction of Dirac states. Furthermore, the small cyclotron mass, high mobility of carriers, and nontrivial Berry's phase are consistent with the presence of Dirac fermions on the side wall of the warped cylindrical Fermi surface. Similarly to SrMnBi2 , which features an anisotropic Dirac cone, our results suggest that magnetic-field-induced changes in interlayer conduction are also present in layered bismuth-based materials with a zero-energy line in momentum space created by the staggered alkaline earth atoms.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20010055260','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20010055260"><span id="translatedtitle">Low Energy <span class="hlt">Electrons</span> in the Mars Plasma <span class="hlt">Environment</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Link, Richard</p> <p>2001-01-01</p> <p>The ionosphere of Mars is rather poorly understood. The only direct measurements were performed by the Viking 1 and 2 landers in 1976, both of which carried a Retarding Potential Analyzer. The RPA was designed to measure ion properties during the descent, although <span class="hlt">electron</span> fluxes were estimated from changes in the ion currents. Using these derived low-energy <span class="hlt">electron</span> fluxes, Mantas and Hanson studied the photoelectron and the solar wind <span class="hlt">electron</span> interactions with the atmosphere and ionosphere of Mars. Unanswered questions remain regarding the origin of the low-energy <span class="hlt">electron</span> fluxes in the vicinity of the Mars plasma boundary. Crider, in an analysis of Mars Global Surveyor Magnetometer/<span class="hlt">Electron</span> Reflectometer measurements, has attributed the formation of the magnetic pile-up boundary to <span class="hlt">electron</span> impact ionization of exospheric neutral species by solar wind <span class="hlt">electrons</span>. However, the role of photoelectrons escaping from the lower ionosphere was not determined. In the proposed work, we will examine the role of solar wind and ionospheric photoelectrons in producing ionization in the upper ionosphere of Mars. Low-energy (< 4 keV) <span class="hlt">electrons</span> will be modeled using the two-stream <span class="hlt">electron</span> <span class="hlt">transport</span> code of Link. The code models both external (solar wind) and internal (photoelectron) sources of ionization, and accounts for Auger <span class="hlt">electron</span> production. The code will be used to analyze Mars Global Surveyor measurements of solar wind and photoelectrons down to altitudes below 200 km in the Mars ionosphere, in order to determine the relative roles of solar wind and escaping photoelectrons in maintaining plasma densities in the region of the Mars plasma boundary.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=246107','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=246107"><span id="translatedtitle">Lipophilic chelator inhibition of <span class="hlt">electron</span> <span class="hlt">transport</span> in Escherichia coli.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Crane, R T; Sun, I L; Crane, F L</p> <p>1975-01-01</p> <p>The lipophilic chelator bathophenanthroline inhibits <span class="hlt">electron</span> <span class="hlt">transport</span> in membranes from Escherichia coli. The less lipophilic 1,10-phenanthroline, bathophenanthroline sulfonate, and alpha,alpha-dipyridyl have little effect. Reduced nicotinamide adenine dinucleotide oxidase is more sensitive to bathophenanthroline inhibition than lactate oxidase activity. Evidence for two sites of inhibition comes from the fact that both reduced nicotinamide adenine dinucleotide menadione reductase and duroquinol oxidase activities are inhibited. Addition of uncouplers of phosphorylation before bathophenanthroline protects against inhibition. PMID:1092663</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2006CP....326..138X','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2006CP....326..138X"><span id="translatedtitle">Redox-gated <span class="hlt">electron</span> <span class="hlt">transport</span> in electrically wired ferrocene molecules</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Xiao, Xiaoyin; Brune, Daniel; He, Jin; Lindsay, Stuart; Gorman, Christopher B.; Tao, Nongjian</p> <p>2006-07-01</p> <p>We have synthesized cysteamine-terminated ferrocene molecules and determined the dependence of the <span class="hlt">electron</span> <span class="hlt">transport</span> properties of the molecules on their redox states by measuring the current through the molecules as a function of the electrode potential. The current fluctuates over a large range, but its average value increases with the potential. We attribute the current fluctuation and its increase with the potential to the switching of the molecules from low-conductance reduced state to high-conductance oxidized state.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/22493833','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/22493833"><span id="translatedtitle"><span class="hlt">Transport</span> of solar <span class="hlt">electrons</span> in the turbulent interplanetary magnetic field</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Ablaßmayer, J.; Tautz, R. C.; Dresing, N.</p> <p>2016-01-15</p> <p>The turbulent <span class="hlt">transport</span> of solar energetic <span class="hlt">electrons</span> in the interplanetary magnetic field is investigated by means of a test-particle Monte-Carlo simulation. The magnetic fields are modeled as a combination of the Parker field and a turbulent component. In combination with the direct calculation of diffusion coefficients via the mean-square displacements, this approach allows one to analyze the effect of the initial ballistic <span class="hlt">transport</span> phase. In that sense, the model complements the main other approach in which a <span class="hlt">transport</span> equation is solved. The major advancement is that, by recording the flux of particles arriving at virtual detectors, intensity and anisotropy-time profiles can be obtained. Observational indications for a longitudinal asymmetry can thus be explained by tracing the diffusive spread of the particle distribution. The approach may be of future help for the systematic interpretation of observations for instance by the solar terrestrial relations observatory (STEREO) and advanced composition explorer (ACE) spacecrafts.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/598594','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/598594"><span id="translatedtitle">Modeling <span class="hlt">electron</span> heat <span class="hlt">transport</span> during magnetic field buildup in SSPX</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Hua, D.D.; Hooper, E.B.; Fowler, T.K.</p> <p>1997-10-01</p> <p>A model for spheromak magnetic field buildup and <span class="hlt">electron</span> thermal <span class="hlt">transport</span>, including a thermal diffusivity associated with magnetic turbulence during helicity injection is applied to a SSPX equilibrium, with a maximum final magnetic field of 1.3 T. Magnetic field-buildup times of 1.0 X 10-3, 5.0 X 10-4 and 1.0 X 10-4 s were used in the model to examine their effects on <span class="hlt">electron</span> thermal <span class="hlt">transport</span>. It is found that at <span class="hlt">transport</span> run time of 4 x 10-3 s, the fastest buildup-time results in the highest final temperature profile, with a core temperature of 0.93 kev while requiring the lowest input energy at 140 KJ. The results show that within the model the most rapid buildup rate generates the highest <span class="hlt">electron</span> temperature at the fastest rate and at the lowest consumption of energy. However, the peak power requirements are large (> 600 MW for the fastest buildup case examined).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/22415564','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/22415564"><span id="translatedtitle">The role of <span class="hlt">electron</span>-impact vibrational excitation in <span class="hlt">electron</span> <span class="hlt">transport</span> through gaseous tetrahydrofuran</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Duque, H. V.; Do, T. P. T.; Konovalov, D. A.; White, R. D.; Brunger, M. J. E-mail: darryl.jones@flinders.edu.au; Jones, D. B. E-mail: darryl.jones@flinders.edu.au</p> <p>2015-03-28</p> <p>In this paper, we report newly derived integral cross sections (ICSs) for <span class="hlt">electron</span> impact vibrational excitation of tetrahydrofuran (THF) at intermediate impact energies. These cross sections extend the currently available data from 20 to 50 eV. Further, they indicate that the previously recommended THF ICS set [Garland et al., Phys. Rev. A 88, 062712 (2013)] underestimated the strength of the <span class="hlt">electron</span>-impact vibrational excitation processes. Thus, that recommended vibrational cross section set is revised to address those deficiencies. <span class="hlt">Electron</span> swarm <span class="hlt">transport</span> properties were calculated with the amended vibrational cross section set, to quantify the role of <span class="hlt">electron</span>-driven vibrational excitation in describing the macroscopic swarm phenomena. Here, significant differences of up to 17% in the <span class="hlt">transport</span> coefficients were observed between the calculations performed using the original and revised cross section sets for vibrational excitation.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/22486307','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/22486307"><span id="translatedtitle"><span class="hlt">Electronic</span> <span class="hlt">transport</span> in VO{sub 2}—Experimentally calibrated Boltzmann <span class="hlt">transport</span> modeling</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Kinaci, Alper; Rosenmann, Daniel; Chan, Maria K. Y. E-mail: mchan@anl.gov; Kado, Motohisa; Ling, Chen; Zhu, Gaohua; Banerjee, Debasish E-mail: mchan@anl.gov</p> <p>2015-12-28</p> <p>Materials that undergo metal-insulator transitions (MITs) are under intense study, because the transition is scientifically fascinating and technologically promising for various applications. Among these materials, VO{sub 2} has served as a prototype due to its favorable transition temperature. While the physical underpinnings of the transition have been heavily investigated experimentally and computationally, quantitative modeling of <span class="hlt">electronic</span> <span class="hlt">transport</span> in the two phases has yet to be undertaken. In this work, we establish a density-functional-theory (DFT)-based approach with Hubbard U correction (DFT + U) to model <span class="hlt">electronic</span> <span class="hlt">transport</span> properties in VO{sub 2} in the semiconducting and metallic regimes, focusing on band <span class="hlt">transport</span> using the Boltzmann <span class="hlt">transport</span> equations. We synthesized high quality VO{sub 2} films and measured the <span class="hlt">transport</span> quantities across the transition, in order to calibrate the free parameters in the model. We find that the experimental calibration of the Hubbard correction term can efficiently and adequately model the metallic and semiconducting phases, allowing for further computational design of MIT materials for desirable <span class="hlt">transport</span> properties.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2007PhDT.......149T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2007PhDT.......149T"><span id="translatedtitle">Charge <span class="hlt">transport</span> and injection in amorphous organic <span class="hlt">electronic</span> materials</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Tse, Shing Chi</p> <p></p> <p>This thesis presents how we use various measuring techniques to study the charge <span class="hlt">transport</span> and injection in organic <span class="hlt">electronic</span> materials. Understanding charge <span class="hlt">transport</span> and injection properties in organic solids is of vital importance for improving performance characteristics of organic <span class="hlt">electronic</span> devices, including organic-light-emitting diodes (OLEDs), photovoltaic cells (OPVs), and field effect transistors (OFETs). The charge <span class="hlt">transport</span> properties of amorphous organic materials, commonly used in organic <span class="hlt">electronic</span> devices, are investigated by the means of carrier mobility measurements. Transient electroluminescence (EL) technique was used to evaluate the <span class="hlt">electron</span> mobility of an <span class="hlt">electron</span> <span class="hlt">transporting</span> material--- tris(8-hydroxyquinoline) aluminum (Alq3). The results are in excellent agreement with independent time-of-flight (TOF) measurements. Then, the effect of dopants on <span class="hlt">electron</span> <span class="hlt">transport</span> was also examined. TOF technique was also used to examine the effects of tertiary-butyl (t-Bu) substitutions on anthracene derivatives (ADN). All ADN compounds were found to be ambipolar. As the degree of t-Bu substitution increases, the carrier mobilities decrease progressively. The reduction of carrier mobilities with increasing t-butylation can be attributed to a decrease in the charge-transfer integral or the wavefunction overlap. In addition, from TOF measurements, two naphthylamine-based hole <span class="hlt">transporters</span>, namely, N,N'-diphenyl-N,N'-bis(1-naphthyl)(1,1'-biphenyl)-4,4'diamine (NPB) and 4,4',4"-tris(n-(2-naphthyl)-n-phenyl-amino)-triphenylamine (2TNATA) were found to possess <span class="hlt">electron-transporting</span> (ET) abilities. An organic light-emitting diode that employed NPB as the ET material was demonstrated. The <span class="hlt">electron</span> conducting mechanism of NPB and 2TNATA in relation to the hopping model will be discussed. Furthermore, the ET property of NPB applied in OLEDs will also be examined. Besides transient EL and TOF techniques, we also use dark-injection space-charge-limited current</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/25909689','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/25909689"><span id="translatedtitle">Theoretical investigations into the <span class="hlt">electronic</span> structures and <span class="hlt">electron</span> <span class="hlt">transport</span> properties of fluorine and carbonyl end-functionalized quarterthiophenes.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Li, Qian; Duan, Yuai; Gao, Hong-Ze; Su, Zhong-Мin; Geng, Yun</p> <p>2015-06-01</p> <p>In this work, we concentrate on systematic investigation on the fluorination and carbonylation effect on <span class="hlt">electron</span> <span class="hlt">transport</span> properties of thiophene-based materials with the aim of seeking and designing <span class="hlt">electron</span> <span class="hlt">transport</span> materials. Some relative factors, namely, frontier molecular orbital (FMO), vertical <span class="hlt">electron</span> affinity (VEA), <span class="hlt">electron</span> reorganization energy (λele), <span class="hlt">electron</span> transfer integral (tele), <span class="hlt">electron</span> drift mobility (μele) and band structures have been calculated and discussed based on density functional theory. The results show that the introduction of fluorine atoms and carbonyl group especially for the latter could effectively increase EA and reduce λele, which is beneficial to the improvement of <span class="hlt">electron</span> <span class="hlt">transport</span> performance. Furthermore, these introductions could also affect the tele by changing molecular packing manner and distribution of FMO. Finally, according to our calculation, the 3d system is considered to be a promising <span class="hlt">electron</span> <span class="hlt">transport</span> material with small λele, high <span class="hlt">electron</span> <span class="hlt">transport</span> ability and good ambient stability.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/23173952','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/23173952"><span id="translatedtitle"><span class="hlt">Electron</span> <span class="hlt">transport</span> in a GaPSb film.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Lo, Shun-Tsung; Lin, Hung En; Wang, Shu-Wei; Lin, Huang-De; Chin, Yu-Chung; Lin, Hao-Hsiung; Lin, Jheng-Cyuan; Liang, Chi-Te</p> <p>2012-11-23</p> <p>We have performed <span class="hlt">transport</span> measurements on a gallium phosphide antimonide (GaPSb) film grown on GaAs. At low temperatures (T), <span class="hlt">transport</span> is governed by three-dimensional Mott variable range hopping (VRH) due to strong localization. Therefore, <span class="hlt">electron-electron</span> interactions are not significant in GaPSb. With increasing T, the coexistence of VRH conduction and the activated behavior with a gap of 20 meV is found. The fact that the measured gap is comparable to the thermal broadening at room temperature (approximately 25 meV) demonstrates that <span class="hlt">electrons</span> can be thermally activated in an intrinsic GaPSb film. Moreover, the observed carrier density dependence on temperature also supports the coexistence of VRH and the activated behavior. It is shown that the carriers are delocalized either with increasing temperature or magnetic field in GaPSb. Our new experimental results provide important information regarding GaPSb which may well lay the foundation for possible GaPSb-based device applications such as in high-<span class="hlt">electron</span>-mobility transistor and heterojunction bipolar transistors.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/25099864','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/25099864"><span id="translatedtitle">Energy level control: toward an efficient hot <span class="hlt">electron</span> <span class="hlt">transport</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Jin, Xiao; Li, Qinghua; Li, Yue; Chen, Zihan; Wei, Tai-Huei; He, Xingdao; Sun, Weifu</p> <p>2014-08-07</p> <p>Highly efficient hot <span class="hlt">electron</span> <span class="hlt">transport</span> represents one of the most important properties required for applications in photovoltaic devices. Whereas the fabrication of efficient hot <span class="hlt">electron</span> capture and lost-cost devices remains a technological challenge, regulating the energy level of acceptor-donor system through the incorporation of foreign ions using the solution-processed technique is one of the most promising strategies to overcome this obstacle. Here we present a versatile acceptor-donor system by incorporating MoO3:Eu nanophosphors, which reduces both the 'excess' energy offset between the conduction band of acceptor and the lowest unoccupied molecular orbital of donor, and that between the valence band and highest occupied molecular orbital. Strikingly, the hot <span class="hlt">electron</span> transfer time has been shortened. This work demonstrates that suitable energy level alignment can be tuned to gain the higher hot <span class="hlt">electron</span>/hole <span class="hlt">transport</span> efficiency in a simple approach without the need for complicated architectures. This work builds up the foundation of engineering building blocks for third-generation solar cells.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4124467','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4124467"><span id="translatedtitle">Energy level control: toward an efficient hot <span class="hlt">electron</span> <span class="hlt">transport</span></span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Jin, Xiao; Li, Qinghua; Li, Yue; Chen, Zihan; Wei, Tai-Huei; He, Xingdao; Sun, Weifu</p> <p>2014-01-01</p> <p>Highly efficient hot <span class="hlt">electron</span> <span class="hlt">transport</span> represents one of the most important properties required for applications in photovoltaic devices. Whereas the fabrication of efficient hot <span class="hlt">electron</span> capture and lost-cost devices remains a technological challenge, regulating the energy level of acceptor-donor system through the incorporation of foreign ions using the solution-processed technique is one of the most promising strategies to overcome this obstacle. Here we present a versatile acceptor-donor system by incorporating MoO3:Eu nanophosphors, which reduces both the ‘excess' energy offset between the conduction band of acceptor and the lowest unoccupied molecular orbital of donor, and that between the valence band and highest occupied molecular orbital. Strikingly, the hot <span class="hlt">electron</span> transfer time has been shortened. This work demonstrates that suitable energy level alignment can be tuned to gain the higher hot <span class="hlt">electron</span>/hole <span class="hlt">transport</span> efficiency in a simple approach without the need for complicated architectures. This work builds up the foundation of engineering building blocks for third-generation solar cells. PMID:25099864</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20030016689','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20030016689"><span id="translatedtitle"><span class="hlt">Electronic</span> Components and Circuits for Extreme Temperature <span class="hlt">Environments</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Patterson, Richard L.; Hammoud, Ahmad; Dickman, John E.; Gerber, Scott</p> <p>2003-01-01</p> <p>Planetary exploration missions and deep space probes require electrical power management and control systems that are capable of efficient and reliable operation in very low temperature <span class="hlt">environments</span>. Presently, spacecraft operating in the cold <span class="hlt">environment</span> of deep space carry a large number of radioisotope heating units in order to maintain the surrounding temperature of the on-board <span class="hlt">electronics</span> at approximately 20 C. <span class="hlt">Electronics</span> capable of operation at cryogenic temperatures will not only tolerate the hostile <span class="hlt">environment</span> of deep space but also reduce system size and weight by eliminating or reducing the radioisotope heating units and their associate structures; thereby reducing system development as well as launch costs. In addition, power <span class="hlt">electronic</span> circuits designed for operation at low temperatures are expected to result in more efficient systems than those at room temperature. This improvement results from better behavior and tolerance in the electrical and thermal properties of semiconductor and dielectric materials at low temperatures. The Low Temperature <span class="hlt">Electronics</span> Program at the NASA Glenn Research Center focuses on research and development of electrical components, circuits, and systems suitable for applications in the aerospace <span class="hlt">environment</span> and deep space exploration missions. Research is being conducted on devices and systems for reliable use down to cryogenic temperatures. Some of the commercial-off-the-shelf as well as developed components that are being characterized include switching devices, resistors, magnetics, and capacitors. Semiconductor devices and integrated circuits including digital-to-analog and analog-to-digital converters, DC/DC converters, operational amplifiers, and oscillators are also being investigated for potential use in low temperature applications. An overview of the NASA Glenn Research Center Low Temperature <span class="hlt">Electronic</span> Program will be presented in this paper. A description of the low temperature test facilities along with</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4738282','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4738282"><span id="translatedtitle">Control of <span class="hlt">electronic</span> <span class="hlt">transport</span> in graphene by electromagnetic dressing</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Kristinsson, K.; Kibis, O. V.; Morina, S.; Shelykh, I. A.</p> <p>2016-01-01</p> <p>We demonstrated theoretically that the renormalization of the <span class="hlt">electron</span> energy spectrum near the Dirac point of graphene by a strong high-frequency electromagnetic field (dressing field) drastically depends on polarization of the field. Namely, linear polarization results in an anisotropic gapless energy spectrum, whereas circular polarization leads to an isotropic gapped one. As a consequence, the stationary (dc) <span class="hlt">electronic</span> <span class="hlt">transport</span> in graphene strongly depends on parameters of the dressing field: A circularly polarized field monotonically decreases the isotropic conductivity of graphene, whereas a linearly polarized one results in both giant anisotropy of conductivity (which can reach thousands of percents) and the oscillating behavior of the conductivity as a function of the field intensity. Since the predicted phenomena can be observed in a graphene layer irradiated by a monochromatic electromagnetic wave, the elaborated theory opens a substantially new way to control <span class="hlt">electronic</span> properties of graphene with light. PMID:26838371</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=1086379','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=1086379"><span id="translatedtitle">Effect of Salts and <span class="hlt">Electron</span> <span class="hlt">Transport</span> on the Conformation of Isolated Chloroplasts. II. <span class="hlt">Electron</span> Microscopy 1</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Izawa, Seikichi; Good, Norman E.</p> <p>1966-01-01</p> <p>Spinach chloroplasts isolated in media containing salts and the rare chloroplasts which are still within their envelopes alike retain grana similar to those seen in chloroplasts in situ. Chloroplasts isolated in low-salt media lose their grana without losing any chlorophyll. These grana-free chloroplasts are considerably swollen and consist almost entirely of continuous sheets of paired-membrane structures. These double structures, the lamellae, are only loosely held together, primarily at the edges, by tenuous material which does not react with permanganate. Addition of salts (methylamine hydrochloride, NaCl, MgCl2) to the grana-free low-salt chloroplasts provide strong interlamellar attractions. These attractions result in a stacking of the lamellae which is sometimes almost random but sometimes results in regular structures indistinguishable from the original grana. The phosphorylation-uncoupler atebrin causes further swelling of the chloroplasts in the absence of <span class="hlt">electron</span> <span class="hlt">transport</span> by increasing the space between the paired membranes of the lamellae. The rapid <span class="hlt">electron</span> <span class="hlt">transport</span> (Hill reaction) made possible by atebrin-uncoupling is associated with a great decrease in chloroplast volume. This decrease results from a collapsing together of the widely separated lamellar membrane pairs. The pairs approach each other so closely that they usually appear as a single membrane when viewed with the <span class="hlt">electron</span> microscope. The much slower <span class="hlt">electron</span> <span class="hlt">transport</span> which occurs in the absence of uncouplers is associated with a similar but smaller decrease in the space between the lamellar membrane pairs. Chloroplasts swell during the rapid <span class="hlt">electron</span> <span class="hlt">transport</span> made possible by the phosphorylation-uncoupler methylamine. This swelling is accompanied by a degree of membrane distortion which precludes an interpretation of the mechanism. As with atebrin-faciliated <span class="hlt">electron</span> <span class="hlt">transport</span>, obviously paired membranes disappear but it is not yet clear whether this is by association or</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2005APS..MARW35003R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2005APS..MARW35003R"><span id="translatedtitle">Tools for Studying <span class="hlt">Electron</span> and Spin <span class="hlt">Transport</span> in Single Molecules</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ralph, Daniel C.</p> <p>2005-03-01</p> <p>Experiments in the field of single-molecule <span class="hlt">electronics</span> are challenging in part because it can be very difficult to control and characterize the device structure. Molecules contacted by metal electrodes cannot easily be imaged by microscopy techniques. Moreover, if one attempts to characterize the device structure simply by measuring a current-voltage curve, it is easy to mistake nonlinear <span class="hlt">transport</span> across a bare tunnel junction or a metallic short for a molecular signal. I will discuss the development of a set of experimental test structures that enable the properties of a molecular device to be tuned controllably in-situ, so that the <span class="hlt">transport</span> mechanisms can be studied more systematically and compared with theoretical predictions. My collaborators and I are developing the means to use several different types of such experimental "knobs" in coordination: electrostatic gating to shift the energy levels in a molecule, mechanical motion to adjust the molecular configuration or the molecule-electrode coupling strength, illumination with light to promote <span class="hlt">electrons</span> to excited states or to make and break chemical bonds, and the use of ferromagnetic electrodes to study spin-polarized <span class="hlt">transport</span>. Our work so far has provided new insights into Kondo physics, the coupling between a molecule's <span class="hlt">electronic</span> and mechanical degrees of freedom, and spin <span class="hlt">transport</span> through a molecule between magnetic electrodes. Collaborators: Radek Bialczak, Alex Champagne, Luke Donev, Jonas Goldsmith, Jacob Grose, Janice Guikema, Jiwoong Park, Josh Parks, Abhay Pasupathy, Jason Petta, Sara Slater, Burak Ulgut, Alexander Soldatov, H'ector Abruña, and Paul McEuen.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li class="active"><span>11</span></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_11 --> <div id="page_12" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li class="active"><span>12</span></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="221"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20080032798','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20080032798"><span id="translatedtitle">Technology Developments in Radiation-Hardened <span class="hlt">Electronics</span> for Space <span class="hlt">Environments</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Keys, Andrew S.; Howell, Joe T.</p> <p>2008-01-01</p> <p>The Radiation Hardened <span class="hlt">Electronics</span> for Space <span class="hlt">Environments</span> (RHESE) project consists of a series of tasks designed to develop and mature a broad spectrum of radiation hardened and low temperature <span class="hlt">electronics</span> technologies. Three approaches are being taken to address radiation hardening: improved material hardness, design techniques to improve radiation tolerance, and software methods to improve radiation tolerance. Within these approaches various technology products are being addressed including Field Programmable Gate Arrays (FPGA), Field Programmable Analog Arrays (FPAA), MEMS, Serial Processors, Reconfigurable Processors, and Parallel Processors. In addition to radiation hardening, low temperature extremes are addressed with a focus on material and design approaches. System level applications for the RHESE technology products are discussed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015PhRvB..91l5419M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015PhRvB..91l5419M"><span id="translatedtitle"><span class="hlt">Electron</span>-vibron coupling effects on <span class="hlt">electron</span> <span class="hlt">transport</span> via a single-molecule magnet</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>McCaskey, Alexander; Yamamoto, Yoh; Warnock, Michael; Burzurí, Enrique; van der Zant, Herre S. J.; Park, Kyungwha</p> <p>2015-03-01</p> <p>We investigate how the <span class="hlt">electron</span>-vibron coupling influences <span class="hlt">electron</span> <span class="hlt">transport</span> via an anisotropic magnetic molecule, such as a single-molecule magnet (SMM) Fe4, by using a model Hamiltonian with parameter values obtained from density-functional theory (DFT). The magnetic anisotropy parameters, vibrational energies, and <span class="hlt">electron</span>-vibron coupling strengths of the Fe4 are computed using DFT. A giant spin model is applied to the Fe4 with only two charge states, specifically a neutral state with a total spin S =5 and a singly charged state with S =9 /2 , which is consistent with our DFT result and experiments on Fe4 single-molecule transistors. In sequential <span class="hlt">electron</span> tunneling, we find that the magnetic anisotropy gives rise to new features in the conductance peaks arising from vibrational excitations. In particular, the peak height shows a strong, unusual dependence on the direction as well as magnitude of applied B field. The magnetic anisotropy also introduces vibrational satellite peaks whose position and height are modified with the direction and magnitude of applied B field. Furthermore, when multiple vibrational modes with considerable <span class="hlt">electron</span>-vibron coupling have energies close to one another, a low-bias current is suppressed, independently of gate voltage and applied B field, although that is not the case for a single mode with a similar <span class="hlt">electron</span>-vibron coupling. In the former case, the conductance peaks reveal a stronger B -field dependence than in the latter case. The new features appear because the magnetic anisotropy barrier is of the same order of magnitude as the energies of vibrational modes with significant <span class="hlt">electron</span>-vibron coupling. Our findings clearly show the interesting interplay between magnetic anisotropy and <span class="hlt">electron</span>-vibron coupling in <span class="hlt">electron</span> <span class="hlt">transport</span> via the Fe4. Similar behavior can be observed in <span class="hlt">transport</span> via other anisotropic magnetic molecules.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/20703910','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/20703910"><span id="translatedtitle">Meeting the ONCHIT population health mandate: a proposed model for security in selective <span class="hlt">transportable</span> distributed <span class="hlt">environments</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Lorence, Daniel; Chin, John; Richards, Michael</p> <p>2010-08-01</p> <p>Goal Two of the US ONCHIT Plan focuses on enabling the use of <span class="hlt">electronic</span> health information for critical health improvement activities that promote the health of targeted communities, and the US population as a whole. Because of the focus on communities and populations, the activities under this second goal differ fundamentally from those of the first goal, which focus on the care of individuals. Proposed here is a model for health information management in such population-based <span class="hlt">environments</span>, which allows selective access and use of information, and maintains <span class="hlt">transportability</span> while ensuring security and confidentiality.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=217209','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=217209"><span id="translatedtitle">Aerotaxis in Salmonella typhimurium: role of <span class="hlt">electron</span> <span class="hlt">transport</span>.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Laszlo, D J; Taylor, B L</p> <p>1981-01-01</p> <p>Sensory transduction in aerotaxis required <span class="hlt">electron</span> <span class="hlt">transport</span>, in contrast to chemotaxis, which is independent of <span class="hlt">electron</span> <span class="hlt">transport</span>. Assays for aerotaxis were developed by employing spatial and temporal oxygen gradients imposed independently of respiration. By varying the step increase in oxygen concentration in the temporal assay, the dose-response relationship was obtained for aerotaxis in Salmonella typhimurium. A half-maximal response at 0.4 microM oxygen and inhibition by 5 mM KCN suggested that the "receptor" for aerotaxis is cytochrome o. The response was independent of adenosine triphosphate formation via oxidative phosphorylation but did correlate with changes in membrane potential monitored with the fluorescent cyanine dye diS-C3-(5). Nitrate and fumarate, which are alternative <span class="hlt">electron</span> acceptors for the respiratory chain in S. typhimurium, inhibited aerotaxis when nitrate reductase and fumarate reductase were induced. These results support the hypothesis that taxis to oxygen, nitrate, and fumarate is mediated by the <span class="hlt">electron</span> <span class="hlt">transport</span> system and by changes in the proton motive force. Aerotaxis was normal in Escherichia coli mutants that were defective in the tsr, tar, or trg genes; in S. typhimurium, oxygen did not stimulate methylation of the products of these genes. A cheC mutant which shows an inverse response to chemoattractants also gave an inverse response to oxygen. Therefore, aerotaxis is transduced by a distinct and unidentified signally protein but is focused into the common chemosensory pathway before the step involving the cheC product. When S. typhimurium became anaerobic, the decreased proton motive force from glycolysis supported slow swimming but not tumbling, indicating that a minimum proton motive force was required for tumbling. The bacteria rapidly adapted to the anaerobic condition and resumed tumbling after about 3 min. The adaptation period was much shorter when the bacteria had been previously grown anaerobically. Images PMID</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014PhRvB..90t5416W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014PhRvB..90t5416W"><span id="translatedtitle"><span class="hlt">Electron</span> <span class="hlt">transport</span> in multiterminal networks of Majorana bound states</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Weithofer, Luzie; Recher, Patrik; Schmidt, Thomas L.</p> <p>2014-11-01</p> <p>We investigate <span class="hlt">electron</span> <span class="hlt">transport</span> through multiterminal networks hosting Majorana bound states (MBS) in the framework of full counting statistics. In particular, we apply our general results to T-shaped junctions of two Majorana nanowires. When the wires are in the topologically nontrivial regime, three MBS are localized near the outer ends of the wires, while one MBS is localized near the crossing point, and when the lengths of the wires are finite adjacent MBS can overlap. We propose a combination of current and cross-correlation measurements to reveal the predicted coupling of four Majoranas in a topological T junction. Interestingly, we show that the elementary <span class="hlt">transport</span> processes at the central lead are different compared to the outer leads, giving rise to characteristic nonlocal signatures in <span class="hlt">electronic</span> <span class="hlt">transport</span>. We find quantitative agreement between our analytical model and numerical simulations of a tight-binding model. Using the numerical simulations, we discuss the effect of weak disorder on the current and the cross-correlation functions.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/accomplishments/documents/fullText/ACC0141.pdf','DOE-RDACC'); return false;" href="http://www.osti.gov/accomplishments/documents/fullText/ACC0141.pdf"><span id="translatedtitle">Helium, Iron and <span class="hlt">Electron</span> Particle <span class="hlt">Transport</span> and Energy <span class="hlt">Transport</span> Studies on the TFTR Tokamak</span></a></p> <p><a target="_blank" href="http://www.osti.gov/accomplishments/fieldedsearch.html">DOE R&D Accomplishments Database</a></p> <p>Synakowski, E. J.; Efthimion, P. C.; Rewoldt, G.; Stratton, B. C.; Tang, W. M.; Grek, B.; Hill, K. W.; Hulse, R. A.; Johnson, D .W.; Mansfield, D. K.; McCune, D.; Mikkelsen, D. R.; Park, H. K.; Ramsey, A. T.; Redi, M. H.; Scott, S. D.; Taylor, G.; Timberlake, J.; Zarnstorff, M. C. (Princeton Univ., NJ (United States). Plasma Physics Lab.); Kissick, M. W. (Wisconsin Univ., Madison, WI (United States))</p> <p>1993-03-01</p> <p>Results from helium, iron, and <span class="hlt">electron</span> <span class="hlt">transport</span> on TFTR in L-mode and Supershot deuterium plasmas with the same toroidal field, plasma current, and neutral beam heating power are presented. They are compared to results from thermal <span class="hlt">transport</span> analysis based on power balance. Particle diffusivities and thermal conductivities are radially hollow and larger than neoclassical values, except possibly near the magnetic axis. The ion channel dominates over the <span class="hlt">electron</span> channel in both particle and thermal diffusion. A peaked helium profile, supported by inward convection that is stronger than predicted by neoclassical theory, is measured in the Supershot The helium profile shape is consistent with predictions from quasilinear electrostatic drift-wave theory. While the perturbative particle diffusion coefficients of all three species are similar in the Supershot, differences are found in the L-Mode. Quasilinear theory calculations of the ratios of impurity diffusivities are in good accord with measurements. Theory estimates indicate that the ion heat flux should be larger than the <span class="hlt">electron</span> heat flux, consistent with power balance analysis. However, theoretical values of the ratio of the ion to <span class="hlt">electron</span> heat flux can be more than a factor of three larger than experimental values. A correlation between helium diffusion and ion thermal <span class="hlt">transport</span> is observed and has favorable implications for sustained ignition of a tokamak fusion reactor.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20070032045','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20070032045"><span id="translatedtitle">High-Performance, Radiation-Hardened <span class="hlt">Electronics</span> for Space <span class="hlt">Environments</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Keys, Andrew S.; Watson, Michael D.; Frazier, Donald O.; Adams, James H.; Johnson, Michael A.; Kolawa, Elizabeth A.</p> <p>2007-01-01</p> <p>The Radiation Hardened <span class="hlt">Electronics</span> for Space <span class="hlt">Environments</span> (RHESE) project endeavors to advance the current state-of-the-art in high-performance, radiation-hardened <span class="hlt">electronics</span> and processors, ensuring successful performance of space systems required to operate within extreme radiation and temperature <span class="hlt">environments</span>. Because RHESE is a project within the Exploration Technology Development Program (ETDP), RHESE's primary customers will be the human and robotic missions being developed by NASA's Exploration Systems Mission Directorate (ESMD) in partial fulfillment of the Vision for Space Exploration. Benefits are also anticipated for NASA's science missions to planetary and deep-space destinations. As a technology development effort, RHESE provides a broad-scoped, full spectrum of approaches to environmentally harden space <span class="hlt">electronics</span>, including new materials, advanced design processes, reconfigurable hardware techniques, and software modeling of the radiation <span class="hlt">environment</span>. The RHESE sub-project tasks are: SelfReconfigurable <span class="hlt">Electronics</span> for Extreme <span class="hlt">Environments</span>, Radiation Effects Predictive Modeling, Radiation Hardened Memory, Single Event Effects (SEE) Immune Reconfigurable Field Programmable Gate Array (FPGA) (SIRF), Radiation Hardening by Software, Radiation Hardened High Performance Processors (HPP), Reconfigurable Computing, Low Temperature Tolerant MEMS by Design, and Silicon-Germanium (SiGe) Integrated <span class="hlt">Electronics</span> for Extreme <span class="hlt">Environments</span>. These nine sub-project tasks are managed by technical leads as located across five different NASA field centers, including Ames Research Center, Goddard Space Flight Center, the Jet Propulsion Laboratory, Langley Research Center, and Marshall Space Flight Center. The overall RHESE integrated project management responsibility resides with NASA's Marshall Space Flight Center (MSFC). Initial technology development emphasis within RHESE focuses on the hardening of Field Programmable Gate Arrays (FPGA)s and Field Programmable Analog</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/950776','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/950776"><span id="translatedtitle">Momentum <span class="hlt">Transport</span> in <span class="hlt">Electron</span>-Dominated Spherical Torus Plasmas</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Kaye, S. M.; Solomon, W.; Bell, R. E.; LeBlanc, B. P.; Levinton, F.; Menard, J.; Rewoldt, G.; Sabbagh, S.; Wang, W.; Yuh, H.</p> <p>2009-02-24</p> <p>The National Spherical Torus Experiment (NSTX) operates between 0.35 and 0.55 T, which, when coupled to up to 7 MW of neutral beam injection, leads to central rotation velocities in excess of 300 km/s and ExB shearing rates up to 1 MHz. This level of ExB shear can be up to a factor of five greater than typical linear growth rates of long-wavelength ion (e.g., ITG) modes, at least partially suppressing these instabilities. Evidence for this turbulence suppression is that the inferred diffusive ion thermal flux in NSTX H-modes is often at the neoclassical level, and thus these plasmas operate in an <span class="hlt">electron</span>-dominated <span class="hlt">transport</span> regime. Analysis of experiments using n=3 magnetic fields to change plasma rotation indicate that local rotation shear influences local <span class="hlt">transport</span> coefficients, most notably the ion thermal diffusivity, in a manner consistent with suppression of the low-k turbulence by this rotation shear. The value of the effective momentum diffusivity, as inferred from steady-state momentum balance, is found to be larger than the neoclassical value. Results of perturbative experiments indicate inward pinch velocities up to 40 m/s and perturbative momentum diffusivities of up to 4 m2/s, which are larger by a factor of several than those values inferred from steady-state analysis. The inferred pinch velocity values are consistent with values based on theories in which low-k turbulence drives the inward momentum pinch. Thus, in Spherical Tori (STs), while the neoclassical ion energy <span class="hlt">transport</span> effects can be relatively high and dominate the ion energy <span class="hlt">transport</span>, the neoclassical momentum <span class="hlt">transport</span> effects are near zero, meaning that <span class="hlt">transport</span> of momentum is dominated by any low-k turbulence that exists.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016JPhCS.774a2103P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016JPhCS.774a2103P"><span id="translatedtitle"><span class="hlt">Transport</span> properties of copper with excited <span class="hlt">electron</span> subsystem</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Petrov, Yu V.; Migdal, K. P.; Knyazev, D. V.; Inogamov, N. A.; Levashov, P. R.</p> <p>2016-11-01</p> <p>We have investigated <span class="hlt">transport</span> properties of an <span class="hlt">electron</span> subsystem of copper heated by a femtosecond laser pulse. These properties change greatly in comparison with the room temperature solid metal. The <span class="hlt">electron</span> temperature and pressure profiles significantly depend on these properties in bulk laser targets according to the two-temperature (2T) model. These profiles at the 2T stage are responsible for shock and rarefaction waves' formation. We have developed the analytical model of electroconductivity and heat conductivity of copper which takes into account changes of density, <span class="hlt">electron</span> and ion temperatures. The model is based on the solution of the Boltzmann equation in the relaxation time approximation for consideration of <span class="hlt">electron</span> collisions. Also we have carried out the first-principles calculations using the Kubo-Greenwood theory, methods of pseudopotential and linear augmented plane waves which are necessary to evaluate <span class="hlt">electron</span> wavefunctions. We have provided the check of convergence of all parameters of our first-principles calculations. The results of our analytical model for electro- and heat conductivities are in good agreement with the data obtained using the linearized augmented plane wave (LAPW) method.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017BGeo...14..683B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017BGeo...14..683B"><span id="translatedtitle">Long-distance <span class="hlt">electron</span> <span class="hlt">transport</span> occurs globally in marine sediments</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Burdorf, Laurine D. W.; Tramper, Anton; Seitaj, Dorina; Meire, Lorenz; Hidalgo-Martinez, Silvia; Zetsche, Eva-Maria; Boschker, Henricus T. S.; Meysman, Filip J. R.</p> <p>2017-02-01</p> <p>Recently, long filamentous bacteria have been reported conducting <span class="hlt">electrons</span> over centimetre distances in marine sediments. These so-called cable bacteria perform an electrogenic form of sulfur oxidation, whereby long-distance <span class="hlt">electron</span> <span class="hlt">transport</span> links sulfide oxidation in deeper sediment horizons to oxygen reduction in the upper millimetres of the sediment. Electrogenic sulfur oxidation exerts a strong impact on the local sediment biogeochemistry, but it is currently unknown how prevalent the process is within the seafloor. Here we provide a state-of-the-art assessment of its global distribution by combining new field observations with previous reports from the literature. This synthesis demonstrates that electrogenic sulfur oxidation, and hence microbial long-distance <span class="hlt">electron</span> <span class="hlt">transport</span>, is a widespread phenomenon in the present-day seafloor. The process is found in coastal sediments within different climate zones (off the Netherlands, Greenland, the USA, Australia) and thrives on a range of different coastal habitats (estuaries, salt marshes, mangroves, coastal hypoxic basins, intertidal flats). The combination of a widespread occurrence and a strong local geochemical imprint suggests that electrogenic sulfur oxidation could be an important, and hitherto overlooked, component of the marine cycle of carbon, sulfur and other elements.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2009SSEle..53.1009S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2009SSEle..53.1009S"><span id="translatedtitle"><span class="hlt">Transport</span> properties in semiconductor-gas discharge <span class="hlt">electronic</span> devices</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Sadiq, Y.; (Yücel) Kurt, H.; Albarzanji, A. O.; Alekperov, S. D.; Salamov, B. G.</p> <p>2009-09-01</p> <p>Nonlinear electrical <span class="hlt">transport</span> of semi-insulating (SI) GaAs detector in semiconductor-gas discharge IR image converter (SGDIC) are studied experimentally for a wide range of the gas pressures ( p = 28-55 Torr), interelectrode distances ( d = 445-525 μm) and inner electrode diameters ( D = 12-22 mm) of photocathode. The destabilization of homogeneous state observed in a planar dc-driven structure is due to nonlinear <span class="hlt">transport</span> properties of GaAs photocathode. Experimental investigation of electrical instability in SGDIC structure was analyzed using hysteresis, N-shaped negative differential conductivity (NDC) current voltage characteristics (CVC) and dynamic behavior of current in a wide range of feeding voltage ( U = 590-1000 V) under different IR light intensities incident on cathode material. It is established that hysteresis are related to <span class="hlt">electron</span> capture and emission from EL2 deep center on the detector substrate. We have experimentally investigated domain velocity and <span class="hlt">electron</span> mobility based on well-understood transferred <span class="hlt">electron</span> effect (TEE) for abovementioned nonlinear electrical characteristics of SI GaAs. The experimental findings are in good agreement with estimated results reported by other independent authors.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012JChPh.136r4301F','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012JChPh.136r4301F"><span id="translatedtitle"><span class="hlt">Electron</span> attachment to molecules in a cluster <span class="hlt">environment</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Fabrikant, I. I.; Caprasecca, S.; Gallup, G. A.; Gorfinkiel, J. D.</p> <p>2012-05-01</p> <p>Low-energy dissociative <span class="hlt">electron</span> attachment (DEA) to the CF2Cl2 and CF3Cl molecules in a water cluster <span class="hlt">environment</span> is investigated theoretically. Calculations are performed for the water trimer and water hexamer. It is shown that the DEA cross section is strongly enhanced when the attaching molecule is embedded in a water cluster, and that this cross section grows as the number of water molecules in the cluster increases. This growth is explained by a trapping effect that is due to multiple scattering by water molecules while the <span class="hlt">electron</span> is trapped in the cluster <span class="hlt">environment</span>. The trapping increases the resonance lifetime and the negative ion survival probability. This confirms qualitatively existing experiments on <span class="hlt">electron</span> attachment to the CF2Cl2 molecule placed on the surface of H2O ice. The DEA cross sections are shown to be very sensitive to the position of the attaching molecule within the cluster and the orientation of the <span class="hlt">electron</span> beam relative to the cluster.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20130013147','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20130013147"><span id="translatedtitle">High Temperature Wireless Communication And <span class="hlt">Electronics</span> For Harsh <span class="hlt">Environment</span> Applications</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Hunter, G. W.; Neudeck, P. G.; Beheim, G. M.; Ponchak, G. E.; Chen, L.-Y</p> <p>2007-01-01</p> <p>In order for future aerospace propulsion systems to meet the increasing requirements for decreased maintenance, improved capability, and increased safety, the inclusion of intelligence into the propulsion system design and operation becomes necessary. These propulsion systems will have to incorporate technology that will monitor propulsion component conditions, analyze the incoming data, and modify operating parameters to optimize propulsion system operations. This implies the development of sensors, actuators, and <span class="hlt">electronics</span>, with associated packaging, that will be able to operate under the harsh <span class="hlt">environments</span> present in an engine. However, given the harsh <span class="hlt">environments</span> inherent in propulsion systems, the development of engine-compatible <span class="hlt">electronics</span> and sensors is not straightforward. The ability of a sensor system to operate in a given <span class="hlt">environment</span> often depends as much on the technologies supporting the sensor element as the element itself. If the supporting technology cannot handle the application, then no matter how good the sensor is itself, the sensor system will fail. An example is high temperature <span class="hlt">environments</span> where supporting technologies are often not capable of operation in engine conditions. Further, for every sensor going into an engine <span class="hlt">environment</span>, i.e., for every new piece of hardware that improves the in-situ intelligence of the components, communication wires almost always must follow. The communication wires may be within or between parts, or from the engine to the controller. As more hardware is added, more wires, weight, complexity, and potential for unreliability is also introduced. Thus, wireless communication combined with in-situ processing of data would significantly improve the ability to include sensors into high temperature systems and thus lead toward more intelligent engine systems. NASA Glenn Research Center (GRC) is presently leading the development of <span class="hlt">electronics</span>, communication systems, and sensors capable of prolonged stable</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/21439580','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/21439580"><span id="translatedtitle">Numerical Investigation of Laser Propulsion for <span class="hlt">Transport</span> in Water <span class="hlt">Environment</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Han Bing; Li Beibei; Zhang Hongchao; Chen Jun; Shen Zhonghua; Lu Jian; Ni Xiaowu</p> <p>2010-10-08</p> <p>Problems that cumber the development of the laser propulsion in atmosphere and vacuum are discussed. Based on the theory of interaction between high-intensity laser and materials, as air and water, it is proved that <span class="hlt">transport</span> in water <span class="hlt">environment</span> can be impulsed by laser. The process of laser propulsion in water is investigated theoretically and numerically. It shows that not only the laser induced plasma shock wave, but also the laser induced bubble oscillation shock waves and the pressure induced by the collapsing bubble can be used. Many experimental results show that the theory and the numerical results are valid. The numerical result of the contribution of every propulsion source is given in percentage. And the maximum momentum coupling coefficient Cm is given. Laser propulsion in water <span class="hlt">environment</span> can be applied in many fields. For example, it can provide highly controllable forces of the order of micro-Newton ({mu}N) in microsystems, such as the MEMS (Micro-electromechanical Systems). It can be used as minimally invasive surgery tools of high temporal and spatial resolution. It can be used as the propulsion source in marine survey and exploitation.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/10183507','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/10183507"><span id="translatedtitle">Studies of local <span class="hlt">electron</span> heat <span class="hlt">transport</span> on TFTR</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Fredrickson, E.D.; Chang, Z.Y.; Janos, A.; McGuire, K.M.; Scott, S.; Taylor, G.</p> <p>1993-08-16</p> <p>The anomalously fast relaxation of the perturbations to the <span class="hlt">electron</span> temperature profile caused by a sawtooth crash has been studied extensively on TFTR. We will show that on a short timescale the heat pulse is not simply diffusive as has been generally assumed, but that modeling of the heat pulse requires a transient enhancement in {chi}{sub e} following the sawtooth crash. It will be shown that the time-dependent enhancement in {chi}{sub e} predicted by non-linear thermal <span class="hlt">transport</span> models, i.e., incremental {chi} models or the Rebut-Lallia-Watkins <span class="hlt">transport</span> model, is much smaller than that required to explain the anomalies in the heat pulse propagation.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2000PhPl....7.2810B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2000PhPl....7.2810B"><span id="translatedtitle">Linear delta-f simulations of nonlocal <span class="hlt">electron</span> heat <span class="hlt">transport</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Brunner, S.; Valeo, E.; Krommes, J. A.</p> <p>2000-07-01</p> <p>Nonlocal <span class="hlt">electron</span> heat <span class="hlt">transport</span> calculations are carried out by making use of some of the techniques developed previously for extending the δf method to <span class="hlt">transport</span> time scale simulations [S. Brunner, E. Valeo, and J. Krommes, Phys. Plasmas 6, 4504 (1999)]. By considering the relaxation of small amplitude temperature perturbations of an homogeneous Maxwellian background, only the linearized Fokker-Planck equation has to be solved, and direct comparisons can be made with the equivalent, nonlocal hydrodynamic approach [V. Yu. Bychenkov et al., Phys. Rev. Lett. 75, 4405 (1995)]. A quasineutrality-conserving algorithm is derived for computing the self-consistent electric fields driving the return currents. In the low-collisionality regime, results illustrate the importance of taking account of nonlocality in both space and time.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/5197113','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/5197113"><span id="translatedtitle">Conservative differencing of the <span class="hlt">electron</span> Fokker-Planck <span class="hlt">transport</span> equation</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Langdon, A.B.</p> <p>1981-01-12</p> <p>We need to extend the applicability and improve the accuracy of kinetic <span class="hlt">electron</span> <span class="hlt">transport</span> codes. In this paper, special attention is given to modelling of e-e collisions, including the dominant contributions arising from anisotropy. The electric field and spatial gradient terms are also considered. I construct finite-difference analogues to the Fokker-Planck integral-differential collision operator, which conserve the particle number, momentum and energy integrals (sums) regardless of the coarseness of the velocity zoning. Such properties are usually desirable, but are especially useful, for example, when there are spatial regions and/or time intervals in which the plasma is cool, so that the collision operator acts rapidly and the velocity distribution is poorly resolved, yet it is crucial that gross conservation properties be respected in hydro-<span class="hlt">transport</span> applications, such as in the LASNEX code. Some points are raised concerning spatial differencing and time integration.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1984PhRvB..29.6879H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1984PhRvB..29.6879H"><span id="translatedtitle">Intersoliton hopping <span class="hlt">transport</span> of <span class="hlt">electrons</span> in molecular crystals</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Howard, I. A.; Conwell, E. M.</p> <p>1984-06-01</p> <p>Quarter-filled-band quasi-one-dimensional compounds which exhibit large Coulomb repulsion between two <span class="hlt">electrons</span> on the same site ("large U") can support the formation of fractionally charged solitons. <span class="hlt">Electron</span> hopping between solitons may contribute substantially to <span class="hlt">transport</span> in these materials. We calculate the intersoliton <span class="hlt">electron</span> hopping rate for transitions mediated by intramolecular phonons and by acoustic phonons. Acoustic phonons are found to be much less effective and are expected to contribute significantly only when intramolecular phonons are not excited or cannot satisfy conservation of energy. For the case of intramolecular phonons, we consider both hopping of an <span class="hlt">electron</span> from a soliton pinned by an impurity to a second soliton which then becomes pinned, and hopping between a pair of solitons, one of which remains free to move. [Owing to the large on-chain dielectric constant (~ 100-1000) in these materials, the solitons are probably not bound except at low temperatures.] The transition rates are used to find the hopping mobility for <span class="hlt">electrons</span> in the soliton levels. Evaluation of the mobility due to the different hopping mechanisms for (N-methylphenazinium)0.54(phenazine)0.46 tetracyanoquinodimethane [(NMP)0.54(Phen)0.46-(TCNQ)] at a temperature of 100 K suggests that, unlike the polyacetylene case, the predominant process at temperatures >~100 K is on-chain hopping, due to the large interchain distances involved. We find a mobility at 100 K of 0.06-1.03 cm2/V sec due to on-chain hopping, mediated by intramolecular phonons, between pinned and free solitons. This mobility should increase at higher temperatures. The thermoelectric power due to the various <span class="hlt">electron</span> hopping processes is calculated as well. We find that for hopping processes involving transitions between pinned and free solitons there is a term in the thermopower involving the soliton pinning energy, in addition to the usual term involving <span class="hlt">electronic</span> energy levels.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.dtic.mil/docs/citations/ADA590300','DTIC-ST'); return false;" href="http://www.dtic.mil/docs/citations/ADA590300"><span id="translatedtitle">Army <span class="hlt">Transportation</span> Systems in a Twenty-First Century Joint Operational <span class="hlt">Environment</span></span></a></p> <p><a target="_blank" href="https://publicaccess.dtic.mil/psm/api/service/search/search">DTIC Science & Technology</a></p> <p></p> <p>2013-03-01</p> <p>Wheeled Vehicles Classification : Unclassified Five components of the U.S. Army <span class="hlt">Transportation</span> Systems collectively meet...Army <span class="hlt">Transportation</span> Systems in a Twenty-First Century Joint Operational <span class="hlt">Environment</span> by Lieutenant Colonel Mark D. Stimer...<span class="hlt">Transportation</span> Systems in a Twenty-First Century Joint Operational <span class="hlt">Environment</span> 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016PhDT.........6B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016PhDT.........6B"><span id="translatedtitle">Nanoscale <span class="hlt">transport</span> of <span class="hlt">electrons</span> and ions in water</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Boynton, Paul Christopher</p> <p></p> <p>The following dissertation discusses the theoretical study of water on the nanoscale, often involved with essential biological molecules such as DNA and proteins. First I introduce the study of water on the nanoscale and how experimentalists approach confinement with nanopores and nanogaps. Then I discuss the theoretical method we choose for understanding this important biological medium on the molecular level, namely classical molecular dynamics. This leads into <span class="hlt">transport</span> mechanisms that utilize water on the nanoscale, in our case <span class="hlt">electronic</span> and ionic <span class="hlt">transport</span>. On the scale of mere nanometers or less <span class="hlt">electronic</span> <span class="hlt">transport</span> in water enters the tunneling regime, requiring the use of a quantum treatment. In addition, I discuss the importance of water in ionic <span class="hlt">transport</span> and its known effects on biological phenomena such as ion selectivity. Water also has great influence over DNA and proteins, which are both introduced in the context of nanopore sequencing. Several techniques for nanopore sequencing are examined and the importance of protein sequencing is explained. In Chapter 2, we study the effect of volumetric constraints on the structure and <span class="hlt">electronic</span> <span class="hlt">transport</span> properties of distilled water in a nanopore with embedded electrodes. Combining classical molecular dynamics simulations with quantum scattering theory, we show that the structural motifs water assumes inside the pore can be probed directly by tunneling. In Chapter 3, we propose an improvement to the original sequencing by tunneling method, in which N pairs of electrodes are built in series along a synthetic nanochannel. Each current time series for each nucleobase is cross-correlated together, reducing noise in the signals. We show using random sampling of data from classical molecular dynamics, that indeed the sequencing error is significantly reduced as the number of pairs of electrodes, N, increases. In Chapter 4, we propose a new technique for de novo protein sequencing that involves translocating a</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li class="active"><span>12</span></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_12 --> <div id="page_13" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li class="active"><span>13</span></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="241"> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/22269317','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/22269317"><span id="translatedtitle">Study of <span class="hlt">electronic</span> <span class="hlt">transport</span> properties of doped 8AGNR</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Sharma, Uma Shankar; Srivastava, Anurag; Verma, U. P.</p> <p>2014-04-24</p> <p>The <span class="hlt">electronic</span> and <span class="hlt">transport</span> properties of 8-armchair graphene nanoribbon (8AGNR) with defect at different sites are investigated by performing first-principles calculations based on density functional theory (DFT). The calculated results show that the 8AGNR are semiconductor. The introduction of 3d transition metals, creates the nondegenerate states in the conduction band, makes 8AGNR metallic. The computed transmission spectrum confirms that AGNR are semiconducting in nature and their band gap remain unchanged and localized states appear when there is vacancy in their structures, and the conductance decreases due to defects compared with the pristine nanoribbon.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/21612543','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/21612543"><span id="translatedtitle">Calculation of <span class="hlt">electronic</span> <span class="hlt">transport</span> coefficients of Ag and Au plasma</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Apfelbaum, E. M.</p> <p>2011-12-15</p> <p>The thermoelectric <span class="hlt">transport</span> coefficients of silver and gold plasma have been calculated within the relaxation-time approximation. We considered temperatures of 10-100 kK and densities of {rho} < or approx. 1 g/cm{sup 3}. The plasma composition was calculated using a corresponding system of coupled mass action laws, including the atom ionization up to +4. For momentum cross sections of <span class="hlt">electron</span>-atom scattering we used the most accurate expressions available. The results of our modeling have been compared with other researchers' data whenever possible.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/11088933','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/11088933"><span id="translatedtitle"><span class="hlt">Electron</span> <span class="hlt">transport</span> in argon in crossed electric and magnetic fields</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Ness; Makabe</p> <p>2000-09-01</p> <p>An investigation of <span class="hlt">electron</span> <span class="hlt">transport</span> in argon in the presence of crossed electric and magnetic fields is carried out over a wide range of values of electric and magnetic field strengths. Values of mean energy, ionization rate, drift velocity, and diffusion tensor are reported here. Two unexpected phenomena arise; for certain values of electric and magnetic field we find regions where the swarm mean energy decreases with increasing electric fields for a fixed magnetic field and regions where swarm mean energy increases with increasing magnetic field for a fixed electric field.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2006APS..MARZ37013T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2006APS..MARZ37013T"><span id="translatedtitle">Theory of <span class="hlt">electron</span>-vibration coupling in the <span class="hlt">electron</span> <span class="hlt">transport</span> of molecular bridges</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Tsukada, Masaru; Mitsutake, Kunihiro</p> <p>2006-03-01</p> <p><span class="hlt">Electron</span> <span class="hlt">transport</span> through molecules connecting nano-electrodes is the key issue for molecular devices. The competition and coexistence of the coherent and dissipative <span class="hlt">transport</span> are unresolved issue, in spite of its importance. In this work, this problem is investigated by a novel theoretical approach of an ab initio molecular orbital model with combining polaron effect. When carriers are injected into molecules from electrodes, the structure of the molecule changes, which leads the coupling term of the <span class="hlt">electron</span>/hole and the molecular vibration. The model Hamiltonian for the thiophene oligomer is solved by a variational approach, and a mixed states of dressed polaron with molecular orbital states mediated by the phonon cloud is found. The former and latter are predominant for small or large transfer integral, respectively. The excited states can be calculated in the same framework as the ground state. The overall carrier <span class="hlt">transport</span> properties can be analyzed by solving the master equation with the transition rate estimated by the golden rule including the phonon degrees of freedom. In this theoretical approach, the coherent and dissipative <span class="hlt">electron</span> <span class="hlt">transport</span> through molecular bridges can be described in a uniform systematic way.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3896775','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3896775"><span id="translatedtitle">Orthogonally modulated molecular <span class="hlt">transport</span> junctions for resettable <span class="hlt">electronic</span> logic gates</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Meng, Fanben; Hervault, Yves-Marie; Shao, Qi; Hu, Benhui; Norel, Lucie; Rigaut, Stéphane; Chen, Xiaodong</p> <p>2014-01-01</p> <p>Individual molecules have been demonstrated to exhibit promising applications as functional components in the fabrication of computing nanocircuits. Based on their advantage in chemical tailorability, many molecular devices with advanced <span class="hlt">electronic</span> functions have been developed, which can be further modulated by the introduction of external stimuli. Here, orthogonally modulated molecular <span class="hlt">transport</span> junctions are achieved via chemically fabricated nanogaps functionalized with dithienylethene units bearing organometallic ruthenium fragments. The addressable and stepwise control of molecular isomerization can be repeatedly and reversibly completed with a judicious use of the orthogonal optical and electrochemical stimuli to reach the controllable switching of conductivity between two distinct states. These photo-/electro-cooperative nanodevices can be applied as resettable <span class="hlt">electronic</span> logic gates for Boolean computing, such as a two-input OR and a three-input AND-OR. The proof-of-concept of such logic gates demonstrates the possibility to develop multifunctional molecular devices by rational chemical design. PMID:24394717</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016PhyE...82..129F','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016PhyE...82..129F"><span id="translatedtitle">Reprint of : Time dependent <span class="hlt">electronic</span> <span class="hlt">transport</span> in chiral edge channels</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Fève, G.; Berroir, J.-M.; Plaçais, B.</p> <p>2016-08-01</p> <p>We study time dependent <span class="hlt">electronic</span> <span class="hlt">transport</span> along the chiral edge channels of the quantum Hall regime, focusing on the role of Coulomb interaction. In the low frequency regime, the a.c. conductance can be derived from a lumped element description of the circuit. At higher frequencies, the propagation equations of the Coulomb coupled edge channels need to be solved. As a consequence of the interchannel coupling, a charge pulse emitted in a given channel fractionalized in several pulses. In particular, Coulomb interaction between channels leads to the fractionalization of a charge pulse emitted in a given channel in several pulses. We finally study how the Coulomb interaction, and in particular the fractionalization process, affects the propagation of a single <span class="hlt">electron</span> in the circuit. All the above-mentioned topics are illustrated by experimental realizations.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017JChPh.146i2302K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017JChPh.146i2302K"><span id="translatedtitle">Structure dependent spin selectivity in <span class="hlt">electron</span> <span class="hlt">transport</span> through oligopeptides</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kiran, Vankayala; Cohen, Sidney R.; Naaman, Ron</p> <p>2017-03-01</p> <p>The chiral-induced spin selectivity (CISS) effect entails spin-selective <span class="hlt">electron</span> transmission through chiral molecules. In the present study, the spin filtering ability of chiral, helical oligopeptide monolayers of two different lengths is demonstrated using magnetic conductive probe atomic force microscopy. Spin-specific nanoscale <span class="hlt">electron</span> <span class="hlt">transport</span> studies elucidate that the spin polarization is higher for 14-mer oligopeptides than that of the 10-mer. We also show that the spin filtering ability can be tuned by changing the tip-loading force applied on the molecules. The spin selectivity decreases with increasing applied force, an effect attributed to the increased ratio of radius to pitch of the helix upon compression and increased tilt angles between the molecular axis and the surface normal. The method applied here provides new insights into the parameters controlling the CISS effect.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016JPhCS.717a2043O','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016JPhCS.717a2043O"><span id="translatedtitle"><span class="hlt">Electron</span> <span class="hlt">transport</span> estimated from <span class="hlt">electron</span> spectra using <span class="hlt">electron</span> spectrometer in LFEX laser target experiments</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ozaki, T.; Hata, M.; Matsuo, K.; Kojima, S.; Arikawa, Y.; Fujioka, S.; Sakagami, H.; Sunahara, A.; Nagatomo, H.; Johzaki, T.; Yogo, A.; Morace, A.; Zhang, Z.; Shiraga, H.; Sakata, S.; Nagai, T.; Abe, Y.; Lee, S.; Nakai, M.; Nishimura, H.; Azechi, H.; FIREX Group; GXII-LFEX Group</p> <p>2016-05-01</p> <p>Hot <span class="hlt">electrons</span> which are generated from targets irradiated by a high-intense laser are measured by two <span class="hlt">electron</span> spectrometers (ESMs). However, total <span class="hlt">electron</span> energy observed by the ESM is only less than 1%. Hot <span class="hlt">electrons</span> are confined by self-fields due to the huge current. When an external magnetic field of several hundred Tesla is applied during the laser irradiation on targets, the ESM signals always increase. In the simulation, the same result can be obtained. The reason is that the Alfvén limit can be mitigated due to the external longitudinal magnetic field.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/763897','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/763897"><span id="translatedtitle">Interfacial Charge <span class="hlt">Transport</span> in Organic <span class="hlt">Electronic</span> Materials: the Key to a New <span class="hlt">Electronics</span> Technology</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Smith, D.L.; Campbell, I.H.; Davids, P.S.; Heller, C.M.; Laurich, B.K.; Crone, B.K.; Saxena, A.; Bishop, A.R.; Ferraris, J.P.; Yu, Z.G.</p> <p>1999-06-04</p> <p>This is the final report of a three-year, Laboratory Directed Research and Development (LDRD) project at Los Alamos National Laboratory (LANL). The primary aim of this project is to obtain a basic scientific understanding of electrical <span class="hlt">transport</span> processes at interfaces that contain an organic <span class="hlt">electronic</span> material. Because of their processing advantages and the tunability of their <span class="hlt">electronic</span> properties, organic <span class="hlt">electronic</span> materials are revolutionizing major technological areas such as information display. We completed an investigation of the fundamental <span class="hlt">electronic</span> excitation energies in the prototype conjugated polymer MEH-PPV. We completed a combined theoretical/experimental study of the energy relation between charged excitations in a conjugated polymer and the metal at a polymer/metal interface. We developed a theoretical model that explains injection currents at polymer/metal interfaces. We have made electrical measurements on devices fabricated using the conjugated polymer MEH-PPV a nd a series of metals.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/15148017','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/15148017"><span id="translatedtitle">Assessing reference staff competency in the <span class="hlt">electronic</span> <span class="hlt">environment</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Munson, Kurt I; Walton, Linda J</p> <p>2004-01-01</p> <p>This paper shows how the Galter Health Sciences Library of Northwestern University's Feinberg School of Medicine developed and implemented a program to assess reference staff competencies for assisting users in the <span class="hlt">electronic</span> <span class="hlt">environment</span> after completing a new training program. The first phase was a year-long assessment of reference questions to identify the types of questions received at the desk. Next, a training program for reference was developed and implemented with an emphasis on answering the most common questions identified such as remote access, access privileges, holdings information, and database searching. The program included individualized instruction on library policies, <span class="hlt">electronic</span> resources, access restrictions, and troubleshooting. The next phase was to create instruments to test staff competencies in answering questions after training. Based on the scores, additional training was individualized and provided to the appropriate staff member to enhance their skills where needed. The training system that was developed has proven to be effective as most staff scored better than 92% on initial testing. As a result, library management can be certain that users' questions are being answered correctly and that the staff has the skills required to work in an <span class="hlt">electronic</span> <span class="hlt">environment</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017PhRvB..95c5430R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017PhRvB..95c5430R"><span id="translatedtitle"><span class="hlt">Electronic</span> <span class="hlt">transport</span> in disordered MoS2 nanoribbons</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ridolfi, Emilia; Lima, Leandro R. F.; Mucciolo, Eduardo R.; Lewenkopf, Caio H.</p> <p>2017-01-01</p> <p>We study the <span class="hlt">electronic</span> structure and <span class="hlt">transport</span> properties of zigzag and armchair monolayer molybdenum disulfide nanoribbons using an 11-band tight-binding model that accurately reproduces the material's bulk band structure near the band gap. We study the <span class="hlt">electronic</span> properties of pristine zigzag and armchair nanoribbons, paying particular attention to the edges states that appear within the MoS2 bulk gap. By analyzing both their orbital composition and their local density of states, we find that in zigzag-terminated nanoribbons these states can be localized at a single edge for certain energies independent of the nanoribbon width. We also study the effects of disorder in these systems using the recursive Green's function technique. We show that for the zigzag nanoribbons, the conductance due to the edge states is strongly suppressed by short-range disorder such as vacancies. In contrast, the local density of states still shows edge localization. We also show that long-range disorder has a small effect on the <span class="hlt">transport</span> properties of nanoribbons within the bulk gap energy window.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/477761','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/477761"><span id="translatedtitle"><span class="hlt">Electron</span> <span class="hlt">transport</span> in coupled double quantum wells and wires</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Harff, N.E.; Simmons, J.A.; Lyo, S.K.</p> <p>1997-04-01</p> <p>Due to inter-quantum well tunneling, coupled double quantum wells (DQWs) contain an extra degree of <span class="hlt">electronic</span> freedom in the growth direction, giving rise to new <span class="hlt">transport</span> phenomena not found in single <span class="hlt">electron</span> layers. This report describes work done on coupled DQWs subject to inplane magnetic fields B{sub {parallel}}, and is based on the lead author`s doctoral thesis, successfully defended at Oregon State University on March 4, 1997. First, the conductance of closely coupled DQWs in B{sub {parallel}} is studied. B{sub {parallel}}-induced distortions in the dispersion, the density of states, and the Fermi surface are described both theoretically and experimentally, with particular attention paid to the dispersion anticrossing and resulting partial energy gap. Measurements of giant distortions in the effective mass are found to agree with theoretical calculations. Second, the Landau level spectra of coupled DQWs in tilted magnetic fields is studied. The magnetoresistance oscillations show complex beating as Landau levels from the two Fermi surface components cross the Fermi level. A third set of oscillations resulting from magnetic breakdown is observed. A semiclassical calculation of the Landau level spectra is then performed, and shown to agree exceptionally well with the data. Finally, quantum wires and quantum point contacts formed in DQW structures are investigated. Anticrossings of the one-dimensional DQW dispersion curves are predicted to have interesting <span class="hlt">transport</span> effects in these devices. Difficulties in sample fabrication have to date prevented experimental verification. However, recently developed techniques to overcome these difficulties are described.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5379059','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5379059"><span id="translatedtitle">Plasmonic hot <span class="hlt">electron</span> <span class="hlt">transport</span> drives nano-localized chemistry</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Cortés, Emiliano; Xie, Wei; Cambiasso, Javier; Jermyn, Adam S.; Sundararaman, Ravishankar; Narang, Prineha; Schlücker, Sebastian; Maier, Stefan A.</p> <p>2017-01-01</p> <p>Nanoscale localization of electromagnetic fields near metallic nanostructures underpins the fundamentals and applications of plasmonics. The unavoidable energy loss from plasmon decay, initially seen as a detriment, has now expanded the scope of plasmonic applications to exploit the generated hot carriers. However, quantitative understanding of the spatial localization of these hot carriers, akin to electromagnetic near-field maps, has been elusive. Here we spatially map hot-<span class="hlt">electron</span>-driven reduction chemistry with 15 nm resolution as a function of time and electromagnetic field polarization for different plasmonic nanostructures. We combine experiments employing a six-<span class="hlt">electron</span> photo-recycling process that modify the terminal group of a self-assembled monolayer on plasmonic silver nanoantennas, with theoretical predictions from first-principles calculations of non-equilibrium hot-carrier <span class="hlt">transport</span> in these systems. The resulting localization of reactive regions, determined by hot-carrier <span class="hlt">transport</span> from high-field regions, paves the way for improving efficiency in hot-carrier extraction science and nanoscale regio-selective surface chemistry. PMID:28348402</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/28348402','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/28348402"><span id="translatedtitle">Plasmonic hot <span class="hlt">electron</span> <span class="hlt">transport</span> drives nano-localized chemistry.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Cortés, Emiliano; Xie, Wei; Cambiasso, Javier; Jermyn, Adam S; Sundararaman, Ravishankar; Narang, Prineha; Schlücker, Sebastian; Maier, Stefan A</p> <p>2017-03-28</p> <p>Nanoscale localization of electromagnetic fields near metallic nanostructures underpins the fundamentals and applications of plasmonics. The unavoidable energy loss from plasmon decay, initially seen as a detriment, has now expanded the scope of plasmonic applications to exploit the generated hot carriers. However, quantitative understanding of the spatial localization of these hot carriers, akin to electromagnetic near-field maps, has been elusive. Here we spatially map hot-<span class="hlt">electron</span>-driven reduction chemistry with 15 nm resolution as a function of time and electromagnetic field polarization for different plasmonic nanostructures. We combine experiments employing a six-<span class="hlt">electron</span> photo-recycling process that modify the terminal group of a self-assembled monolayer on plasmonic silver nanoantennas, with theoretical predictions from first-principles calculations of non-equilibrium hot-carrier <span class="hlt">transport</span> in these systems. The resulting localization of reactive regions, determined by hot-carrier <span class="hlt">transport</span> from high-field regions, paves the way for improving efficiency in hot-carrier extraction science and nanoscale regio-selective surface chemistry.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/25071080','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/25071080"><span id="translatedtitle">Dirac model of <span class="hlt">electronic</span> <span class="hlt">transport</span> in graphene antidot barriers.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Thomsen, M R; Brun, S J; Pedersen, T G</p> <p>2014-08-20</p> <p>In order to use graphene for semiconductor applications, such as transistors with high on/off ratios, a band gap must be introduced into this otherwise semimetallic material. A promising method of achieving a band gap is by introducing nanoscale perforations (antidots) in a periodic pattern, known as a graphene antidot lattice (GAL). A graphene antidot barrier (GAB) can be made by introducing a 1D GAL strip in an otherwise pristine sheet of graphene. In this paper, we will use the Dirac equation (DE) with a spatially varying mass term to calculate the <span class="hlt">electronic</span> <span class="hlt">transport</span> through such structures. Our approach is much more general than previous attempts to use the Dirac equation to calculate scattering of Dirac <span class="hlt">electrons</span> on antidots. The advantage of using the DE is that the computational time is scale invariant and our method may therefore be used to calculate properties of arbitrarily large structures. We show that the results of our Dirac model are in quantitative agreement with tight-binding for hexagonal antidots with armchair edges. Furthermore, for a wide range of structures, we verify that a relatively narrow GAB, with only a few antidots in the unit cell, is sufficient to give rise to a <span class="hlt">transport</span> gap.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/1343313','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/1343313"><span id="translatedtitle">ecode - <span class="hlt">Electron</span> <span class="hlt">Transport</span> Algorithm Testing v. 1.0</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Franke, Brian C.; Olson, Aaron J.; Bruss, Donald Eugene; Laub, Thomas W.; Crawford, Martin J; Kenseck, Ronald P.; Prinja, Anil</p> <p>2016-10-05</p> <p>ecode is a Monte Carlo code used for testing algorithms related to <span class="hlt">electron</span> <span class="hlt">transport</span>. The code can read basic physics parameters, such as energy-dependent stopping powers and screening parameters. The code permits simple planar geometries of slabs or cubes. Parallelization consists of domain replication, with work distributed at the start of the calculation and statistical results gathered at the end of the calculation. Some basic routines (such as input parsing, random number generation, and statistics processing) are shared with the Integrated Tiger Series codes. A variety of algorithms for uncertainty propagation are incorporated based on the stochastic collocation and stochastic Galerkin methods. These permit uncertainty only in the total and angular scattering cross sections. The code contains algorithms for simulating stochastic mixtures of two materials. The physics is approximate, ranging from mono-energetic and isotropic scattering to screened Rutherford angular scattering and Rutherford energy-loss scattering (simple <span class="hlt">electron</span> <span class="hlt">transport</span> models). No production of secondary particles is implemented, and no photon physics is implemented.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/787905','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/787905"><span id="translatedtitle">Simulations of <span class="hlt">Electron</span> <span class="hlt">Transport</span> in Laser Hot Spots</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>S. Brunner; E. Valeo</p> <p>2001-08-30</p> <p>Simulations of <span class="hlt">electron</span> <span class="hlt">transport</span> are carried out by solving the Fokker-Planck equation in the diffusive approximation. The system of a single laser hot spot, with open boundary conditions, is systematically studied by performing a scan over a wide range of the two relevant parameters: (1) Ratio of the stopping length over the width of the hot spot. (2) Relative importance of the heating through inverse Bremsstrahlung compared to the thermalization through self-collisions. As for uniform illumination [J.P. Matte et al., Plasma Phys. Controlled Fusion 30 (1988) 1665], the bulk of the velocity distribution functions (VDFs) present a super-Gaussian dependence. However, as a result of spatial <span class="hlt">transport</span>, the tails are observed to be well represented by a Maxwellian. A similar dependence of the distributions is also found for multiple hot spot systems. For its relevance with respect to stimulated Raman scattering, the linear Landau damping of the <span class="hlt">electron</span> plasma wave is estimated for such VD Fs. Finally, the nonlinear Fokker-Planck simulations of the single laser hot spot system are also compared to the results obtained with the linear non-local hydrodynamic approach [A.V. Brantov et al., Phys. Plasmas 5 (1998) 2742], thus providing a quantitative limit to the latter method: The hydrodynamic approach presents more than 10% inaccuracy in the presence of temperature variations of the order delta T/T greater than or equal to 1%, and similar levels of deformation of the Gaussian shape of the Maxwellian background.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014APS..MARF29007L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014APS..MARF29007L"><span id="translatedtitle"><span class="hlt">Electronic</span> <span class="hlt">transport</span> in graphene sheets in a random magnetic field</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Lewenkopf, Caio; Burgos, Rhonald; Warnes, Jesus; Lima, Leandro</p> <p>2014-03-01</p> <p>We present a theoretical study of the effect of ripples and strain fields in the <span class="hlt">transport</span> properties of diffusive deposited graphene flakes. Defects in the crystalline structure, adsorbed atomic impurities and charge inhomogeneities at the substrate are believed to be the dominant disorder sources for the <span class="hlt">electronic</span> <span class="hlt">transport</span> in graphene at low temperatures. We show that intrinsic ripples also effect the conductivity, in particular, its quantum corrections. To this end, we analyze recent experimental results on the conductivity of rippled monolayer graphene sheets subjected to a strong magnetic field parallel to the graphene-substrate interface, B∥ [M. B. Lundeberg and J. A. Folk, Phys. Rev. Lett. 105, 146804 (2010)]. In this setting, B∥ gives rise to a random magnetic field normal to graphene sheet, that depends on the local curvature of the smooth disordered ripples. The analysis of the weak localization corrections of the magnetoconductance allows to establish the dependence of <span class="hlt">electronic</span> dephasing rate on the magnitude of the random magnetic field. We compare the results for B∥ with the conductivity and weak localization corrections due to the pseudo-magnetic fields originated by intrinsic ripples and strain fields.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/266736','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/266736"><span id="translatedtitle">Space applications of the MITS <span class="hlt">electron</span>-photon Monte Carlo <span class="hlt">transport</span> code system</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Kensek, R.P.; Lorence, L.J.; Halbleib, J.A.; Morel, J.E.</p> <p>1996-07-01</p> <p>The MITS multigroup/continuous-energy <span class="hlt">electron</span>-photon Monte Carlo <span class="hlt">transport</span> code system has matured to the point that it is capable of addressing more realistic three-dimensional adjoint applications. It is first employed to efficiently predict point doses as a function of source energy for simple three-dimensional experimental geometries exposed to simulated uniform isotropic planar sources of monoenergetic <span class="hlt">electrons</span> up to 4.0 MeV. Results are in very good agreement with experimental data. It is then used to efficiently simulate dose to a detector in a subsystem of a GPS satellite due to its natural <span class="hlt">electron</span> <span class="hlt">environment</span>, employing a relatively complex model of the satellite. The capability for survivability analysis of space systems is demonstrated, and results are obtained with and without variance reduction.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014PhRvB..90c5445F','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014PhRvB..90c5445F"><span id="translatedtitle">Real-space method for highly parallelizable <span class="hlt">electronic</span> <span class="hlt">transport</span> calculations</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Feldman, Baruch; Seideman, Tamar; Hod, Oded; Kronik, Leeor</p> <p>2014-07-01</p> <p>We present a real-space method for first-principles nanoscale <span class="hlt">electronic</span> <span class="hlt">transport</span> calculations. We use the nonequilibrium Green's function method with density functional theory and implement absorbing boundary conditions (ABCs, also known as complex absorbing potentials, or CAPs) to represent the effects of the semi-infinite leads. In real space, the Kohn-Sham Hamiltonian matrix is highly sparse. As a result, the <span class="hlt">transport</span> problem parallelizes naturally and can scale favorably with system size, enabling the computation of conductance in relatively large molecular junction models. Our use of ABCs circumvents the demanding task of explicitly calculating the leads' self-energies from surface Green's functions, and is expected to be more accurate than the use of the jellium approximation. In addition, we take advantage of the sparsity in real space to solve efficiently for the Green's function over the entire energy range relevant to low-bias <span class="hlt">transport</span>. We illustrate the advantages of our method with calculations on several challenging test systems and find good agreement with reference calculation results.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li class="active"><span>13</span></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_13 --> <div id="page_14" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li class="active"><span>14</span></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="261"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016APS..GECMW6035D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016APS..GECMW6035D"><span id="translatedtitle">Third order <span class="hlt">transport</span> coefficients for <span class="hlt">electrons</span> and positrons in gases</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Dujko, Sasa; Simonovic, Ilija; White, Ronald; Petrovic, Zoran</p> <p>2016-09-01</p> <p>Third order <span class="hlt">transport</span> coefficients (the skewness tensor) of the <span class="hlt">electron</span> and positron swarms, in atomic and molecular gases, are investigated. The knowledge of the skewness tensor is necessary for the conversion of the hydrodynamic <span class="hlt">transport</span> coefficients to the arrival time and steady-state Townsend <span class="hlt">transport</span> data as well as for the determination of the deviations of the spatial density profiles from an ideal Gaussian. In this work, we investigate the structure and symmetries along individual elements of the skewness tensor by the group projector method. Individual components of the skewness tensor are calculated using a Monte Carlo simulation technique and multi term theory for solving the Boltzmann equation. Results obtained by these two methods are in excellent agreement. We extend previous studies by considering the sensitivity of the skewness components to explicit and implicit effects of non-conservative collisions, post-ionization energy partitioning, and inelastic collisions. The errors of the two term approximation for solving the Boltzmann equation are highlighted. We also investigate the influence of a magnetic field on the skewness tensor in varying configurations of electric and magnetic fields. Among many interesting points, we have observed a strong correlation between the skewness and diffusion.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2006PhDT.......246M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2006PhDT.......246M"><span id="translatedtitle">Low-dimensional <span class="hlt">electron</span> <span class="hlt">transport</span> in mesoscopic semiconductor devices</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Martin, Theodore Peyton</p> <p></p> <p>Recent advances in solid state materials engineering have led to mesoscopic devices with feature sizes that approach the fundamental quantum wavelength of charge carriers in the solid, allowing for the experimental observation of quantum interference. By confining carriers to a single quantum state in one or more dimensions, the degrees of freedom for charge <span class="hlt">transport</span> can be reduced to achieve new device functionality. This dissertation focuses on mesoscopic <span class="hlt">electron</span> billiards that combine the aspects of zero, one, and two-dimensional <span class="hlt">transport</span> into one system. Low-temperature measurement of billiards fabricated within a relatively defect-free semiconductor heterostructure results in ballistic <span class="hlt">transport</span>, where the <span class="hlt">electron</span> waves follow classical trajectories and the confining walls play a major role in determining the <span class="hlt">electron</span> interference. Billiards have been traditionally formed by applying a bias to patterned surface gates atop an AlGaAs/GaAs heterostructure. Within this system, fractal fluctuations in the billiard conductance are observed as a function of an applied external magnetic field. These fluctuations are tied to quantum interference via an empirical parameter that describes the resolution of energy levels within the billiard. To investigate whether fractal fluctuations are a robust phenomenon intrinsic to billiard-like structures, this study centers on billiards defined by etching walls into a GaInAs/InP heterostructure, departing from the traditional system in both the type of confinement and material system used. It is expected that etched walls will provide a steeper confinement profile leading to well-defined device shapes. Conductance measurements through the one-dimensional leads that couple <span class="hlt">electrons</span> into the billiard are utilized in combination with a self-consistent Schrodinger/Poisson solution to demonstrate a steeper confinement potential. Experiments are also carried out to determine whether fractal fluctuations persist when billiards are</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010cosp...38.1889S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010cosp...38.1889S"><span id="translatedtitle"><span class="hlt">Electron</span> <span class="hlt">transport</span> in the solar wind -results from numerical simulations</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Smith, Håkan; Marsch, Eckart; Helander, Per</p> <p></p> <p>A conventional fluid approach is in general insufficient for a correct description of <span class="hlt">electron</span> <span class="hlt">trans-port</span> in weakly collisional plasmas such as the solar wind. The classical Spitzer-Hürm theory is a not valid when the Knudsen number (the mean free path divided by the length scale of tem-perature variation) is greater than ˜ 10-2 . Despite this, the heat <span class="hlt">transport</span> from Spitzer-Hürm a theory is widely used in situations with relatively long mean free paths. For realistic Knud-sen numbers in the solar wind, the <span class="hlt">electron</span> distribution function develops suprathermal tails, and the departure from a local Maxwellian can be significant at the energies which contribute the most to the heat flux moment. To accurately model heat <span class="hlt">transport</span> a kinetic approach is therefore more adequate. Different techniques have been used previously, e.g. particle sim-ulations [Landi, 2003], spectral methods [Pierrard, 2001], the so-called 16 moment method [Lie-Svendsen, 2001], and approximation by kappa functions [Dorelli, 2003]. In the present study we solve the Fokker-Planck equation for <span class="hlt">electrons</span> in one spatial dimension and two velocity dimensions. The distribution function is expanded in Laguerre polynomials in energy, and a finite difference scheme is used to solve the equation in the spatial dimension and the velocity pitch angle. The ion temperature and density profiles are assumed to be known, but the electric field is calculated self-consistently to guarantee quasi-neutrality. The kinetic equation is of a two-way diffusion type, for which the distribution of particles entering the computational domain in both ends of the spatial dimension must be specified, leaving the outgoing distributions to be calculated. The long mean free path of the suprathermal <span class="hlt">electrons</span> has the effect that the details of the boundary conditions play an important role in determining the particle and heat fluxes as well as the electric potential drop across the domain. Dorelli, J. C., and J. D. Scudder, J. D</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20110015809','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20110015809"><span id="translatedtitle">Modeling Ionosphere <span class="hlt">Environments</span>: Creating an ISS <span class="hlt">Electron</span> Density Tool</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Gurgew, Danielle N.; Minow, Joseph I.</p> <p>2011-01-01</p> <p>The International Space Station (ISS) maintains an altitude typically between 300 km and 400 km in low Earth orbit (LEO) which itself is situated in the Earth's ionosphere. The ionosphere is a region of partially ionized gas (plasma) formed by the photoionization of neutral atoms and molecules in the upper atmosphere of Earth. It is important to understand what <span class="hlt">electron</span> density the spacecraft is/will be operating in because the ionized gas along the ISS orbit interacts with the electrical power system resulting in charging of the vehicle. One instrument that is already operational onboard the ISS with a goal of monitoring <span class="hlt">electron</span> density, <span class="hlt">electron</span> temperature, and ISS floating potential is the Floating Potential Measurement Unit (FPMU). Although this tool is a valuable addition to the ISS, there are limitations concerning the data collection periods. The FPMU uses the Ku band communication frequency to transmit data from orbit. Use of this band for FPMU data runs is often terminated due to necessary observation of higher priority Extravehicular Activities (EVAs) and other operations on ISS. Thus, large gaps are present in FPMU data. The purpose of this study is to solve the issue of missing environmental data by implementing a secondary <span class="hlt">electron</span> density data source, derived from the COSMIC satellite constellation, to create a model of ISS orbital <span class="hlt">environments</span>. Extrapolating data specific to ISS orbital altitudes, we model the ionospheric <span class="hlt">electron</span> density along the ISS orbit track to supply a set of data when the FPMU is unavailable. This computer model also provides an additional new source of <span class="hlt">electron</span> density data that is used to confirm FPMU is operating correctly and supplements the original environmental data taken by FPMU.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015APS..DFDL30004G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015APS..DFDL30004G"><span id="translatedtitle">Energy and water vapor <span class="hlt">transport</span> in a turbulent stratified <span class="hlt">environment</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Gallana, Luca; de Santi, Francesca; Iovieno, Michele; Richiardone, Renzo; Tordella, Daniela</p> <p>2015-11-01</p> <p>We present direct numerical simulations about the <span class="hlt">transport</span> of kinetic energy and unsaturated water vapor across a thin layer which separates two decaying turbulent flows with different energy. This interface lies in a shearless stratified <span class="hlt">environment</span> modeled by means of Boussinesq's approximation. Water vapor is treated as a passive scalar (Kumar et al. 2014). Initial conditions have Fr2 between 0.64 and 64 (stable case) and between -3.2 and -19 (unstable case) and Reλ = 250 . Dry air is in the lower half of the domain and has a higher turbulent energy, seven times higher than the energy of moist air in the upper half. In the early stage of evolution, as long as | F r2 | > 1 , stratification plays a minor role and the flows follows closely neutral stratification mixing. As the buoyancy terms grows, Fr2 ~ O (1) , the mixing process deeply changes. A stable stratification generates a separation layer which blocks the entrainment of dry air into the moist one, characterized by a relative increment of the turbulent dissipation rate compared to the local turbulent energy. On the contrary, an unstable stratification sligthy enhances the entrainment. Growth-decay of energy and mixing layer thichness are discussed and compared with laboratory and numerical experiments.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/7030210','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/7030210"><span id="translatedtitle">Severe shock and vibration <span class="hlt">environments</span> for <span class="hlt">electronic</span> components</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Martinez, D.R.</p> <p>1990-01-01</p> <p><span class="hlt">Electronic</span> components used in system applications must be qualified to mechanical shock and vibration <span class="hlt">environments</span>. Often these <span class="hlt">environments</span> are severe, requiring the development and use of special test techniques and procedures. Environmental specifications are based upon analytical model predictions and measured test data. Test specifications are determined after careful consideration of simulation techniques, input levels, dynamic behavior of the test fixturing, as well as an assessment of the degree of conservatism imposed by the specification and testing procedures. The process of determining component shock and vibration specifications is discussed, beginning with the initial description of system and subsystem level <span class="hlt">environments</span>, and concluding with component level test specifications. Included is a discussion of the difference between environmental specifications and test specifications, and the instrumentation/measurement problems associated with obtaining valid field measurements for severe shock data. The role of finite element analysis in predicting the dynamic structural response of components is also explained. Shock data analysis techniques are described including both time-domain and frequency-domain characterizations of the data. The resonant plate shock testing technique for simulating severe shock <span class="hlt">environments</span> is presented, including difficulties that arise in practical applications. 18 refs., 10 figs.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/23331168','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/23331168"><span id="translatedtitle">When <span class="hlt">electron</span> transfer meets <span class="hlt">electron</span> <span class="hlt">transport</span> in redox-active molecular nanojunctions.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Janin, Marion; Ghilane, Jalal; Lacroix, Jean-Christophe</p> <p>2013-02-13</p> <p>A scanning electrochemical microscope (SECM) was used to arrange two microelectrodes face-to-face separated by a micrometric gap. Polyaniline (PANI) was deposited electrochemically from the SECM tip side until it bridged the two electrodes. The junctions obtained were characterized by following the current through the PANI as a function of its electrochemical potential measured versus a reference electrode acting as a gate electrode in a solid-state transistor. PANI nanojunctions showed conductances below 100 nS in the oxidized state, indicating control of the charge <span class="hlt">transport</span> within the whole micrometric gap by a limited number of PANI wires. The SECM configuration makes it possible to observe in the same experiment and in the same current range the <span class="hlt">electron</span>-transfer and <span class="hlt">electron-transport</span> processes. These two phenomena are distinguished here and characterized by following the variation of the current with the bias voltage and the scan rate. The <span class="hlt">electron</span>-transfer current changes with the scan rate, while the charge-<span class="hlt">transport</span> current varies with the bias voltage. Finally, despite the initially micrometric gap, a junction where the conductance is controlled by a single oligoaniline strand is achieved.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/22062328','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/22062328"><span id="translatedtitle">Integrated <span class="hlt">electronic</span> <span class="hlt">transport</span> and thermometry at milliKelvin temperatures and in strong magnetic fields</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Samkharadze, N.; Kumar, A.; Csathy, G. A.; Manfra, M. J.; Pfeiffer, L. N.; West, K. W.</p> <p>2011-05-15</p> <p>We fabricated a He-3 immersion cell for <span class="hlt">transport</span> measurements of semiconductor nanostructures at ultra low temperatures and in strong magnetic fields. We have a new scheme of field-independent thermometry based on quartz tuning fork Helium-3 viscometry which monitors the local temperature of the sample's <span class="hlt">environment</span> in real time. The operation and measurement circuitry of the quartz viscometer is described in detail. We provide evidence that the temperature of two-dimensional <span class="hlt">electron</span> gas confined to a GaAs quantum well follows the temperature of the quartz viscometer down to 4 mK.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/21639513','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/21639513"><span id="translatedtitle">Integrated <span class="hlt">electronic</span> <span class="hlt">transport</span> and thermometry at milliKelvin temperatures and in strong magnetic fields.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Samkharadze, N; Kumar, A; Manfra, M J; Pfeiffer, L N; West, K W; Csáthy, G A</p> <p>2011-05-01</p> <p>We fabricated a He-3 immersion cell for <span class="hlt">transport</span> measurements of semiconductor nanostructures at ultra low temperatures and in strong magnetic fields. We have a new scheme of field-independent thermometry based on quartz tuning fork Helium-3 viscometry which monitors the local temperature of the sample's <span class="hlt">environment</span> in real time. The operation and measurement circuitry of the quartz viscometer is described in detail. We provide evidence that the temperature of two-dimensional <span class="hlt">electron</span> gas confined to a GaAs quantum well follows the temperature of the quartz viscometer down to 4 mK.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016JPhCS.720a2046D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016JPhCS.720a2046D"><span id="translatedtitle">Parallel processing implementation for the coupled <span class="hlt">transport</span> of photons and <span class="hlt">electrons</span> using OpenMP</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Doerner, Edgardo</p> <p>2016-05-01</p> <p>In this work the use of OpenMP to implement the parallel processing of the Monte Carlo (MC) simulation of the coupled <span class="hlt">transport</span> for photons and <span class="hlt">electrons</span> is presented. This implementation was carried out using a modified EGSnrc platform which enables the use of the Microsoft Visual Studio 2013 (VS2013) <span class="hlt">environment</span>, together with the developing tools available in the Intel Parallel Studio XE 2015 (XE2015). The performance study of this new implementation was carried out in a desktop PC with a multi-core CPU, taking as a reference the performance of the original platform. The results were satisfactory, both in terms of scalability as parallelization efficiency.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2006JChPh.124c4708J','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2006JChPh.124c4708J"><span id="translatedtitle">A generalized quantum chemical approach for elastic and inelastic <span class="hlt">electron</span> <span class="hlt">transports</span> in molecular <span class="hlt">electronics</span> devices</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Jiang, Jun; Kula, Mathias; Luo, Yi</p> <p>2006-01-01</p> <p>A generalized quantum chemical approach for <span class="hlt">electron</span> <span class="hlt">transport</span> in molecular devices is developed. It allows one to treat devices where the metal electrodes and the molecule are either chemically or physically bonded on equal footing. An extension to include the vibration motions of the molecule has also been implemented which has produced the inelastic <span class="hlt">electron</span>-tunneling spectroscopy of molecular <span class="hlt">electronics</span> devices with unprecedented accuracy. Important information about the structure of the molecule and of metal-molecule contacts that are not accessible in the experiment are revealed. The calculated current-voltage (I-V) characteristics of different molecular devices, including benzene-1,4-dithiolate, octanemonothiolate [H(CH2)8S], and octanedithiolate [S(CH2)8S] bonded to gold electrodes, are in very good agreement with experimental measurements.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/22262617','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/22262617"><span id="translatedtitle"><span class="hlt">Electron-electron</span> interaction, weak localization and spin valve effect in vertical-<span class="hlt">transport</span> graphene devices</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Long, Mingsheng; Gong, Youpin; Wei, Xiangfei; Zhu, Chao; Xu, Jianbao; Liu, Ping; Guo, Yufen; Li, Weiwei; Liu, Liwei; Liu, Guangtong</p> <p>2014-04-14</p> <p>We fabricated a vertical structure device, in which graphene is sandwiched between two asymmetric ferromagnetic electrodes. The measurements of <span class="hlt">electron</span> and spin <span class="hlt">transport</span> were performed across the combined channels containing the vertical and horizontal components. The presence of <span class="hlt">electron-electron</span> interaction (EEI) was found not only at low temperatures but also at moderate temperatures up to ∼120 K, and EEI dominates over weak localization (WL) with and without applying magnetic fields perpendicular to the sample plane. Moreover, spin valve effect was observed when magnetic filed is swept at the direction parallel to the sample surface. We attribute the EEI and WL surviving at a relatively high temperature to the effective suppress of phonon scattering in the vertical device structure. The findings open a way for studying quantum correlation at relatively high temperature.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20110008233&hterms=proton&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3Dproton','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20110008233&hterms=proton&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3Dproton"><span id="translatedtitle">A Deterministic <span class="hlt">Electron</span>, Photon, Proton and Heavy Ion Radiation <span class="hlt">Transport</span> Suite for the Study of the Jovian System</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Norman, Ryan B.; Badavi, Francis F.; Blattnig, Steve R.; Atwell, William</p> <p>2011-01-01</p> <p>A deterministic suite of radiation <span class="hlt">transport</span> codes, developed at NASA Langley Research Center (LaRC), which describe the <span class="hlt">transport</span> of <span class="hlt">electrons</span>, photons, protons, and heavy ions in condensed media is used to simulate exposures from spectral distributions typical of <span class="hlt">electrons</span>, protons and carbon-oxygen-sulfur (C-O-S) trapped heavy ions in the Jovian radiation <span class="hlt">environment</span>. The particle <span class="hlt">transport</span> suite consists of a coupled <span class="hlt">electron</span> and photon deterministic <span class="hlt">transport</span> algorithm (CEPTRN) and a coupled light particle and heavy ion deterministic <span class="hlt">transport</span> algorithm (HZETRN). The primary purpose for the development of the <span class="hlt">transport</span> suite is to provide a means for the spacecraft design community to rapidly perform numerous repetitive calculations essential for <span class="hlt">electron</span>, proton and heavy ion radiation exposure assessments in complex space structures. In this paper, the radiation <span class="hlt">environment</span> of the Galilean satellite Europa is used as a representative boundary condition to show the capabilities of the <span class="hlt">transport</span> suite. While the <span class="hlt">transport</span> suite can directly access the output <span class="hlt">electron</span> spectra of the Jovian <span class="hlt">environment</span> as generated by the Jet Propulsion Laboratory (JPL) Galileo Interim Radiation <span class="hlt">Electron</span> (GIRE) model of 2003; for the sake of relevance to the upcoming Europa Jupiter System Mission (EJSM), the 105 days at Europa mission fluence energy spectra provided by JPL is used to produce the corresponding dose-depth curve in silicon behind an aluminum shield of 100 mils ( 0.7 g/sq cm). The <span class="hlt">transport</span> suite can also accept ray-traced thickness files from a computer-aided design (CAD) package and calculate the total ionizing dose (TID) at a specific target point. In that regard, using a low-fidelity CAD model of the Galileo probe, the <span class="hlt">transport</span> suite was verified by comparing with Monte Carlo (MC) simulations for orbits JOI--J35 of the Galileo extended mission (1996-2001). For the upcoming EJSM mission with a potential launch date of 2020, the <span class="hlt">transport</span> suite is used to compute</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/22482256','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/22482256"><span id="translatedtitle">Density-dependent <span class="hlt">electron</span> <span class="hlt">transport</span> and precise modeling of GaN high <span class="hlt">electron</span> mobility transistors</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Bajaj, Sanyam Shoron, Omor F.; Park, Pil Sung; Krishnamoorthy, Sriram; Akyol, Fatih; Hung, Ting-Hsiang; Reza, Shahed; Chumbes, Eduardo M.; Khurgin, Jacob; Rajan, Siddharth</p> <p>2015-10-12</p> <p>We report on the direct measurement of two-dimensional sheet charge density dependence of <span class="hlt">electron</span> <span class="hlt">transport</span> in AlGaN/GaN high <span class="hlt">electron</span> mobility transistors (HEMTs). Pulsed IV measurements established increasing <span class="hlt">electron</span> velocities with decreasing sheet charge densities, resulting in saturation velocity of 1.9 × 10{sup 7 }cm/s at a low sheet charge density of 7.8 × 10{sup 11 }cm{sup −2}. An optical phonon emission-based <span class="hlt">electron</span> velocity model for GaN is also presented. It accommodates stimulated longitudinal optical (LO) phonon emission which clamps the <span class="hlt">electron</span> velocity with strong <span class="hlt">electron</span>-phonon interaction and long LO phonon lifetime in GaN. A comparison with the measured density-dependent saturation velocity shows that it captures the dependence rather well. Finally, the experimental result is applied in TCAD-based device simulator to predict DC and small signal characteristics of a reported GaN HEMT. Good agreement between the simulated and reported experimental results validated the measurement presented in this report and established accurate modeling of GaN HEMTs.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.gpo.gov/fdsys/pkg/CFR-2013-title32-vol6/pdf/CFR-2013-title32-vol6-sec2001-23.pdf','CFR2013'); return false;" href="https://www.gpo.gov/fdsys/pkg/CFR-2013-title32-vol6/pdf/CFR-2013-title32-vol6-sec2001-23.pdf"><span id="translatedtitle">32 CFR 2001.23 - Classification marking in the <span class="hlt">electronic</span> <span class="hlt">environment</span>.</span></a></p> <p><a target="_blank" href="http://www.gpo.gov/fdsys/browse/collectionCfr.action?selectedYearFrom=2013&page.go=Go">Code of Federal Regulations, 2013 CFR</a></p> <p></p> <p>2013-07-01</p> <p>... INFORMATION SECURITY OVERSIGHT OFFICE, NATIONAL ARCHIVES AND RECORDS ADMINISTRATION CLASSIFIED NATIONAL SECURITY INFORMATION Identification and Markings § 2001.23 Classification marking in the <span class="hlt">electronic</span> <span class="hlt">environment</span>. (a) General. Classified national security information in the <span class="hlt">electronic</span> <span class="hlt">environment</span> shall be:...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.gpo.gov/fdsys/pkg/CFR-2011-title32-vol6/pdf/CFR-2011-title32-vol6-sec2001-23.pdf','CFR2011'); return false;" href="https://www.gpo.gov/fdsys/pkg/CFR-2011-title32-vol6/pdf/CFR-2011-title32-vol6-sec2001-23.pdf"><span id="translatedtitle">32 CFR 2001.23 - Classification marking in the <span class="hlt">electronic</span> <span class="hlt">environment</span>.</span></a></p> <p><a target="_blank" href="http://www.gpo.gov/fdsys/browse/collectionCfr.action?selectedYearFrom=2011&page.go=Go">Code of Federal Regulations, 2011 CFR</a></p> <p></p> <p>2011-07-01</p> <p>... INFORMATION SECURITY OVERSIGHT OFFICE, NATIONAL ARCHIVES AND RECORDS ADMINISTRATION CLASSIFIED NATIONAL SECURITY INFORMATION Identification and Markings § 2001.23 Classification marking in the <span class="hlt">electronic</span> <span class="hlt">environment</span>. (a) General. Classified national security information in the <span class="hlt">electronic</span> <span class="hlt">environment</span> shall be:...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/21180303','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/21180303"><span id="translatedtitle">Correlation between <span class="hlt">Electron</span> <span class="hlt">Transport</span> and Shear Alfven Activity in the National Spherical Torus Experiment</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Stutman, D.; Delgado-Aparicio, L.; Finkenthal, M.; Tritz, K.; Gorelenkov, N.; Fredrickson, E.; Kaye, S.; Mazzucato, E.</p> <p>2009-03-20</p> <p>We report the observation of a correlation between shear Alfven eigenmode activity and <span class="hlt">electron</span> <span class="hlt">transport</span> in plasma regimes where the <span class="hlt">electron</span> temperature gradient is flat, and thus the drive for temperature gradient microinstabilities is absent. Plasmas having rapid central <span class="hlt">electron</span> <span class="hlt">transport</span> show intense, broadband global Alfven eigenmode (GAE) activity in the 0.5-1.1 MHz range, while plasmas with low <span class="hlt">transport</span> are essentially GAE-free. The first theoretical assessment of a GAE-<span class="hlt">electron</span> <span class="hlt">transport</span> connection indicates that overlapping modes can resonantly couple to the bulk thermal <span class="hlt">electrons</span> and induce their stochastic diffusion.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/984468','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/984468"><span id="translatedtitle">Anomalous <span class="hlt">Electron</span> <span class="hlt">Transport</span> Due to Multiple High Frequency Beam Ion Driven Alfven Eigenmode</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Gorelenkov, N. N.; Stutman, D.; Tritz, K.; Boozer, A.; Delgardo-Aparicio, L.; Fredrickson, E.; Kaye, S.; White, R.</p> <p>2010-07-13</p> <p>We report on the simulations of recently observed correlations of the core <span class="hlt">electron</span> <span class="hlt">transport</span> with the sub-thermal ion cyclotron frequency instabilities in low aspect ratio plasmas of the National Spherical Torus Experiment (NSTX). In order to model the <span class="hlt">electron</span> <span class="hlt">transport</span> of the guiding center code ORBIT is employed. A spectrum of test functions of multiple core localized Global shear Alfven Eigenmode (GAE) instabilities based on a previously developed theory and experimental observations is used to examine the <span class="hlt">electron</span> <span class="hlt">transport</span> properties. The simulations exhibit thermal <span class="hlt">electron</span> <span class="hlt">transport</span> induced by <span class="hlt">electron</span> drift orbit stochasticity in the presence of multiple core localized GAE.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/1009202','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/1009202"><span id="translatedtitle">Hot <span class="hlt">Electron</span> Generation and <span class="hlt">Transport</span> Using K(alpha) Emission</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Akli, K U; Stephens, R B; Key, M H; Bartal, T; Beg, F N; Chawla, S; Chen, C D; Fedosejevs, R; Freeman, R R; Friesen, H; Giraldez, E; Green, J S; Hey, D S; Higginson, D P; Hund, J; Jarrott, L C; Kemp, G E; King, J A; Kryger, A; Lancaster, K; LePape, S; Link, A; Ma, T; Mackinnon, A J; MacPhee, A G; McLean, H S; Murphy, C; Norreys, P A; Ovchinnikov, V; Patel, P K; Ping, Y; Sawada, H; Schumacher, D; Theobald, W; Tsui, Y Y; Van Woerkom, L D; Wei, M S; Westover, B; Yabuuchi, T</p> <p>2009-10-15</p> <p>We have conducted experiments on both the Vulcan and Titan laser facilities to study hot <span class="hlt">electron</span> generation and <span class="hlt">transport</span> in the context of fast ignition. Cu wires attached to Al cones were used to investigate the effect on coupling efficiency of plasma surround and the pre-formed plasma inside the cone. We found that with thin cones 15% of laser energy is coupled to the 40{micro}m diameter wire emulating a 40{micro}m fast ignition spot. Thick cone walls, simulating plasma in fast ignition, reduce coupling by x4. An increase of prepulse level inside the cone by a factor of 50 reduces coupling by a factor of 3.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/26196817','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/26196817"><span id="translatedtitle">Pauli-Heisenberg Oscillations in <span class="hlt">Electron</span> Quantum <span class="hlt">Transport</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Thibault, Karl; Gabelli, Julien; Lupien, Christian; Reulet, Bertrand</p> <p>2015-06-12</p> <p>We measure the current fluctuations emitted by a normal-metal-insulator-normal-metal tunnel junction with a very wide bandwidth, from 0.3 to 13 GHz, down to very low temperature T=35  mK. This allows us to perform the spectroscopy (i.e., measure the frequency dependence) of thermal noise (no dc bias, variable temperature) and shot noise (low temperature, variable dc voltage bias). Because of the very wide bandwidth of our measurement, we deduce the current-current correlator in the time domain. We observe the thermal decay of this correlator as well as its oscillations with a period h/eV, a direct consequence of the effect of the Pauli and Heisenberg principles in quantum <span class="hlt">electron</span> <span class="hlt">transport</span>.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li class="active"><span>14</span></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_14 --> <div id="page_15" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li class="active"><span>15</span></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="281"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016ChPhB..25c7309H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016ChPhB..25c7309H"><span id="translatedtitle">Velocity modulation of <span class="hlt">electron</span> <span class="hlt">transport</span> through a ferromagnetic silicene junction</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Huai-Hua, Shao; Dan, Guo; Ben-Liang, Zhou; Guang-Hui, Zhou</p> <p>2016-03-01</p> <p>We address velocity-modulation control of <span class="hlt">electron</span> wave propagation in a normal/ferromagnetic/normal silicene junction with local variation of Fermi velocity, where the properties of charge, valley, and spin <span class="hlt">transport</span> through the junction are investigated. By matching the wavefunctions at the normal-ferromagnetic interfaces, it is demonstrated that the variation of Fermi velocity in a small range can largely enhance the total conductance while keeping the current nearly fully valley- and spin-polarized. Further, the variation of Fermi velocity in ferromagnetic silicene has significant influence on the valley and spin polarization, especially in the low-energy regime. It may drastically reduce the high polarizations, which can be realized by adjusting the local application of a gate voltage and exchange field on the junction. Project supported by the National Natural Science Foundation of China (Grant No. 11274108).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016APS..MAR.F5008Q','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016APS..MAR.F5008Q"><span id="translatedtitle"><span class="hlt">Electronic</span> measurement of strain effects on spin <span class="hlt">transport</span> in silicon</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Qing, Lan; Tinkey, Holly; Appelbaum, Ian</p> <p></p> <p>Spin <span class="hlt">transport</span> in silicon is limited by the Elliott-Yafet spin relaxation mechanism, which is driven by scattering between degenerate conduction band valleys. Mechanical strain along a valley axis partially breaks this degeneracy, and will ultimately quench intervalley spin relaxation for transitions between states on orthogonal axes. Using a custom-designed and constructed strain probe, we study the effects of uniaxial compressive strain along the < 100 > direction on ballistic tunnel junction devices used to inject spin-polarized <span class="hlt">electrons</span> into silicon. The effects of strain-induced valley splitting will be presented and compared to our theoretical model. This work is supported by the Office of Naval Research under Contract No. N000141410317, the National Science Foundation under Contract No. ECCS-1231855, the Defense Threat Reduction Agency under Contract No. HDTRA1-13-1-0013, and the Maryland NanoCenter.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015PhPro..75..948D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015PhPro..75..948D"><span id="translatedtitle">Relativistic Effects on <span class="hlt">Electron</span> <span class="hlt">Transport</span> in Magnetic Alloys</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Drchal, Václav; Kudrnovský, Josef; Turek, Ilja</p> <p></p> <p>We study the relativistic effects on <span class="hlt">electron</span> <span class="hlt">transport</span> in spin-polarized metals and random alloys on ab initio level using the fully relativistic tight-binding linear muffin-tin-orbital (TB-LMTO) method. We employ a Kubo linear-response approach adapted to disordered multisublattice systems in which the chemical disorder is described in terms of the coherent potential approximation (CPA). The CPA vertex corrections are included. We calculate both the Fermi surface and Fermi sea terms of the full conductivity tensor. We find that in cubic ferromagnetic 3d transition metals (Fe, Co, Ni) and their random binary alloys (Ni-Fe, Fe-Si) the Fermi sea term in the anomalous Hall conductivity is small in comparison with the Fermi surface term, however, in more complicated structures, such as hexagonal Co and selected Co-based Heusler alloys, it becomes important. We find an overall good agreement between the theory and experimental data.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016EPJB...89..191Z','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016EPJB...89..191Z"><span id="translatedtitle"><span class="hlt">Electronic</span> <span class="hlt">transport</span> properties of a quinone-based molecular switch</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Zheng, Ya-Peng; Bian, Bao-An; Yuan, Pei-Pei</p> <p>2016-09-01</p> <p>In this paper, we carried out first-principles calculations based on density functional theory and non-equilibrium Green's function to investigate the <span class="hlt">electronic</span> <span class="hlt">transport</span> properties of a quinone-based molecule sandwiched between two Au electrodes. The molecular switch can be reversibly switched between the reduced hydroquinone (HQ) and oxidized quinone (Q) states via redox reactions. The switching behavior of two forms is analyzed through their I- V curves, transmission spectra and molecular projected self-consistent Hamiltonian at zero bias. Then we discuss the transmission spectra of the HQ and Q forms at different bias, and explain the oscillation of current according to the transmission eigenstates of LUMO energy level for Q form. The results suggest that this kind of a quinone-based molecule is usable as one of the good candidates for redox-controlled molecular switches.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016APS..MARC26001B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016APS..MARC26001B"><span id="translatedtitle"><span class="hlt">Electron</span> <span class="hlt">Transport</span> Simulations of 4-Terminal Crossed Graphene Nanoribbons Devices</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Brandimarte, Pedro; Papior, Nick R.; Engelund, Mads; Garcia-Lekue, Aran; Frederiksen, Thomas; Sánchez-Portal, Daniel</p> <p></p> <p>Recently, it has been reported theoretically a current switching mechanism by voltage control in a system made by two perpendicular 14-armchair graphene nanoribbons (GNRs). In order to investigate the possibilities of using crossed GNRs as ON/OFF devices, we have studied their <span class="hlt">electronic</span> and <span class="hlt">transport</span> properties as function structural parameters determining the crossing. Our calculations were performed with TranSIESTA code, which has been recently generalized to consider N >= 1 arbitrarily distributed electrodes at finite bias. We find that the transmission along each individual GNR and among them strongly depends on the stacking. For a 60° rotation angle, the lattice matching in the crossing region provokes a strong scattering effect that translates into an increased interlayer transmission. FP7 FET-ICT PAMS-project (European Commission, contract 610446), MINECO (Grant MAT2013-46593-C6-2-P) and Basque Dep. de Educación, UPV/EHU (Grant IT-756-13).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/22492133','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/22492133"><span id="translatedtitle">Conformation dependent <span class="hlt">electronic</span> <span class="hlt">transport</span> in a DNA double-helix</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Kundu, Sourav Karmakar, S. N.</p> <p>2015-10-15</p> <p>We present a tight-binding study of conformation dependent <span class="hlt">electronic</span> <span class="hlt">transport</span> properties of DNA double-helix including its helical symmetry. We have studied the changes in the localization properties of DNA as we alter the number of stacked bases within every pitch of the double-helix keeping fixed the total number of nitrogen bases within the DNA molecule. We take three DNA sequences, two of them are periodic and one is random and observe that in all the cases localization length increases as we increase the radius of DNA double-helix i.e., number of nucleobases within a pitch. We have also investigated the effect of backbone energetic on the I-V response of the system and found that in presence of helical symmetry, depending on the interplay of conformal variation and disorder, DNA can be found in either metallic, semiconducting and insulating phases, as observed experimentally.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20090014179&hterms=DSP&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D60%26Ntt%3DDSP','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20090014179&hterms=DSP&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D60%26Ntt%3DDSP"><span id="translatedtitle">Re-Configurable <span class="hlt">Electronics</span> Characterization under Extreme Thermal <span class="hlt">Environment</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Stoica, Adrian; Lacayo, Veronica; Ramesham, Rajeshuni; Keymeulen, Didier; Zebulum, Ricardo; Neff, Joe; Burke, Gary; Daud, Taher</p> <p>2005-01-01</p> <p>The need for reconfigurable <span class="hlt">electronics</span> is driven by requirements to survive longer missions and harsher <span class="hlt">environments</span>. It is possible to compensate for degradations in Extreme <span class="hlt">Environments</span> (EE). EE has effect on <span class="hlt">electronics</span>: circuits are designed to exploit device characteristics and when a certain temperature or radiation range is exceeded the circuit function gradually degrades. It is possible to employ Hardening by reconfiguration (HBR) to mitigate drifts, degradation, or damage on <span class="hlt">electronic</span> devices in EE by using reconfigurable devices and an adaptive self-reconfiguration of circuit topology. In this manner degraded components can be salvaged, and completely damaged components can be bypassed. The challenge of conventional design is replaced with that of designing a recover process that automatically performs the (re) design in place of the designer. The objective of testing a Digital Signal Processor (DSP) under the extreme temperatures was to determine the lowest temperature at which the DAP can operate. The objective of testing a Xilinx VirtexII Pro FPGA board was to initially find our whether the evaluation board and the FPGA would survive and continue at temperature ranges from -180 C, and 120 C. The Virtex II functioned correctly at the temperatures tested. The next test was done on the GM-C filter building block using the same temperature range as the Virtex II. The current lower and upper limits were shown to be reduced as the temperature gets lower. The device function can be recovered by increasing the Vb from .08V to .85V. The negative and positive saturation voltages increases as the temperature gets higher. The function of the device can be recovered by decreasing the Vb from .8V to around .75V. The next test was performed to test the recovery of the GmC low pass filter through Vb in a filter circuit. The test indicate that bias voltage control adjustment is an efficient mechanism for circuit recovery at extreme temperatures.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2008PhDT.......107L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2008PhDT.......107L"><span id="translatedtitle">Quantum chaos and <span class="hlt">electron</span> <span class="hlt">transport</span> properties in a quantum waveguide</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Lee, Hoshik</p> <p></p> <p>We numerically investigate <span class="hlt">electron</span> <span class="hlt">transport</span> properties in an <span class="hlt">electron</span> waveguide which can be constructed in 2DEG of the heterostructure of GaAs and AlGaAs. We apply R-matrix theory to solve a Schrodinger equation and construct a S-matrix, and we then calculate conductance of an <span class="hlt">electron</span> waveguide. We study single impurity scattering in a waveguide. A delta-function model as a single impurity is very attractive, but it has been known that delta-function potential does not give a convergent result in two or higher space dimensions. However, we find that it can be used as a single impurity in a waveguide with the truncation of the number of modes. We also compute conductance for a finite size impurity by using R-matrix theory. We propose an appropriate criteria for determining the cut-off mode for a delta-function impurity that reproduces the conductance of a waveguide when a finite impurity presents. We find quantum scattering echoes in a ripple waveguide. A ripple waveguide (or cavity) is widely used for quantum chaos studies because it is easy to control a particle's dynamics. Moreover we can obtain an exact expression of Hamiltonian matrix with for the waveguide using a simple coordinate transformation. Having an exact Hamiltonian matrix reduces computation time significantly. It saves a lot of computational needs. We identify three families of resonance which correspond to three different classical phase space structures. Quasi bound states of one of those resonances reside on a hetero-clinic tangle formed by unstable manifolds and stable manifolds in the phase space of a corresponding classical system. Resonances due to these states appear in the conductance in a nearly periodic manner as a function of energy. Period from energy frequency gives a good agreement with a prediction of the classical theory. We also demonstrate wavepacket dynamics in a ripple waveguide. We find quantum echoes in the transmitted probability of a wavepacket. The period of echoes also</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/1238384','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/1238384"><span id="translatedtitle">Radiation Hardened <span class="hlt">Electronics</span> Destined For Severe Nuclear Reactor <span class="hlt">Environments</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Holbert, Keith E.; Clark, Lawrence T.</p> <p>2016-02-19</p> <p>Post nuclear accident conditions represent a harsh <span class="hlt">environment</span> for <span class="hlt">electronics</span>. The full station blackout experience at Fukushima shows the necessity for emergency sensing capabilities in a radiation-enhanced <span class="hlt">environment</span>. This NEET (Nuclear Energy Enabling Technologies) research project developed radiation hardened by design (RHBD) <span class="hlt">electronics</span> using commercially available technology that employs commercial off-the-shelf (COTS) devices and present generation circuit fabrication techniques to improve the total ionizing dose (TID) hardness of <span class="hlt">electronics</span>. Such technology not only has applicability to severe accident conditions but also to facilities throughout the nuclear fuel cycle in which radiation tolerance is required. For example, with TID tolerance to megarads of dose, <span class="hlt">electronics</span> could be deployed for long-term monitoring, inspection and decontamination missions. The present work has taken a two-pronged approach, specifically, development of both board and application-specific integrated circuit (ASIC) level RHBD techniques. The former path has focused on TID testing of representative microcontroller ICs with embedded flash (eFlash) memory, as well as standalone flash devices that utilize the same fabrication technologies. The standalone flash devices are less complicated, allowing better understanding of the TID response of the crucial circuits. Our TID experiments utilize biased components that are in-situ tested, and in full operation during irradiation. A potential pitfall in the qualification of memory circuits is the lack of rigorous testing of the possible memory states. For this reason, we employ test patterns that include all ones, all zeros, a checkerboard of zeros and ones, an inverse checkerboard, and random data. With experimental evidence of improved radiation response for unbiased versus biased conditions, a demonstration-level board using the COTS devices was constructed. Through a combination of redundancy and power gating, the demonstration</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1986PhRvB..34.2158K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1986PhRvB..34.2158K"><span id="translatedtitle"><span class="hlt">Transport</span> of <span class="hlt">electron</span>-hole plasma in germanium</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kirch, S. J.; Wolfe, J. P.</p> <p>1986-08-01</p> <p>Time-resolved luminescence imaging techniques are used to observe the spectral and spatial evolution of laser-generated <span class="hlt">electron</span>-hole plasma in Ge. Both pulsed and cw excitation conditions are examined above and below the critical temperature for <span class="hlt">electron</span>-hole liquid formation, Tc(LG). For Q-switched Nd-doped yttrium aluminum garnet laser excitation, the <span class="hlt">transport</span> behavior is qualitatively similar above and below Tc(LG), although the luminescence spectrum undergoes significant changes in this temperature range. A rapid initial expansion (v~105 cm/s) is followed by a period of slower growth which gradually reduces as the carriers recombine. The initial velocity for pulsed excitation increases monotonically as the crystal temperature is lowered and saturates near the phonon sound velocity for high-energy excitation. These observations are consistent with phonon-wind driven <span class="hlt">transport</span>. For intense Q-switched excitation, the motion is characterized by three regimes: (1) During the laser pulse the plasma expands as a large drop with near-unity filling fraction. (2) Expansion at near-sonic velocity continues after the peak of the laser pulse due to a ``prompt'' pulse of ballistic phonons produced by the carrier thermalization process. (3) After this intense phonon wind passes the carrier distribution, the expansion velocity abruptly decreases, but the plasma continues to expand more slowly under the influence of a ``hot spot'' produced at the excitation point. The sound barrier observed on these time scales (>=30 ns) can be explained in terms of nonlinear damping of the plasma motion near the sound velocity. For cw excitation, the expansion is observed to occur at much lower velocities (v~104 cm/s). These expansion rates are much too low to require the inclusion of a drifted Fermi distribution in the spectral analysis as has been previously suggested. Instead, based upon a careful study of corresponding spectral data, an alternative explanation for these spectra is</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2009PhDT.......167B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2009PhDT.......167B"><span id="translatedtitle">Characterization of ionic <span class="hlt">transport</span> in polymer and <span class="hlt">electronic</span> <span class="hlt">transport</span> in disordered selenium and ceramic materials</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Bandyopadhyay, Subhasish</p> <p></p> <p>In this thesis, the properties of <span class="hlt">electronic</span> conduction in vanadium (donor) and scandium (acceptor) doped Ba0.7Sr0.3TiO3 ceramics, amorphous Selenium and ionic conduction in polyester polyol based polyurethane have been investigated. The leakage current of bulk vanadium (donor) and scandium (acceptor) doped Ba0.7Sr0.3TiO3 ceramics structures measured using gold electrical contacts have been characterized and analyzed. Vanadium doping reduces the ohmic leakage current that dominates the <span class="hlt">transport</span> characteristics up to 5 kV/cm. The Arrhenius activation energy is 0.18, 0.20 and 0.23 eV for 1, 2 and 4 at % V-doped samples, respectively. Above this field, the current-voltage characteristics exhibit discontinuous current transitions associated with trap filling by <span class="hlt">electronic</span> carriers. At higher fields, trap controlled space charge limited conduction (SCLC) is observed with an effective mobility of 4+/-1x10-7 cm2/V s, characteristic of <span class="hlt">electronic</span> <span class="hlt">transport</span> process that involves quasi equilibrium between conduction in the band and trapping. In contrast, the leakage current of Sc-doped samples increases with impurity concentration and exhibits a 0.60 eV activation energy. In this case, the limiting current conduction mechanism is the <span class="hlt">transport</span> of holes over the electrostatic barrier at grain boundaries. Comparison of these results to those on similarly-doped homoepitaxial SrTiO3 thin-films deposited on single-crystal and bicrystal substrates helped to identify the characteristics of <span class="hlt">transport</span> in the bulk and across grain boundaries for this class of materials. Electrical, thermal and Li <span class="hlt">transport</span> properties have been measured for polyester polyol and isocyanate-based polyurethanes doped with Lithium trifluoromethanesulfonimide (LiTFSI) and Lithium perchlorate (LiClO4) Electrical conductivities are estimated at 10-5--10-6 S/cm near 300 K. The conductivities show Vogel-Tammann-Fulcher (VTF) behavior over a wide temperature ranges. Differential scanning calorimetry (DSC) shows</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/22493896','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/22493896"><span id="translatedtitle"><span class="hlt">Electron</span> <span class="hlt">transport</span> in molecular junctions with graphene as protecting layer</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Hüser, Falco; Solomon, Gemma C.</p> <p>2015-12-07</p> <p>We present ab initio <span class="hlt">transport</span> calculations for molecular junctions that include graphene as a protecting layer between a single molecule and gold electrodes. This vertical setup has recently gained significant interest in experiment for the design of particularly stable and reproducible devices. We observe that the signals from the molecule in the <span class="hlt">electronic</span> transmission are overlayed by the signatures of the graphene sheet, thus raising the need for a reinterpretation of the transmission. On the other hand, we see that our results are stable with respect to various defects in the graphene. For weakly physiosorbed molecules, no signs of interaction with the graphene are evident, so the <span class="hlt">transport</span> properties are determined by offresonant tunnelling between the gold leads across an extended structure that includes the molecule itself and the additional graphene layer. Compared with pure gold electrodes, calculated conductances are about one order of magnitude lower due to the increased tunnelling distance. Relative differences upon changing the end group and the length of the molecule on the other hand, are similar.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2005JaJAP..44..523L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2005JaJAP..44..523L"><span id="translatedtitle">Intrinsic <span class="hlt">Electronic</span> <span class="hlt">Transport</span> through Alkanedithiol Self-Assembled Monolayer</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Lee, Takhee; Wang, Wenyong; Reed, Mark A.</p> <p>2005-01-01</p> <p><span class="hlt">Electronic</span> <span class="hlt">transport</span> through an alkanedithiol self-assembled monolayer (SAM) is investigated using a nanometer scale device. Temperature-independent current-voltage characteristics are observed, indicating tunneling is the main conduction mechanism. The measured current-voltage characteristics are analyzed with a metal-insulator-metal tunneling model. The inelastic <span class="hlt">electron</span> tunneling spectroscopy (IETS) study on the octanedithiol device clearly shows the vibrational signatures of molecules. The pronounced IETS peaks correspond to vibrational modes perpendicular to the junction interface, which include the stretching modes of Au-S (at 33 mV) and C-C (at 133 mV), and wagging mode of CH2 (at 158 mV). Intrinsic linewidths are determined as 1.69 (upper limit), 3.73± 0.98, and 13.5± 2.4 meV for Au-S, C-C streching modes, and CH2 wagging mode, respectively. The observed peak intensities and peak widths are in good agreement with theoretical predictions.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/28147541','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/28147541"><span id="translatedtitle"><span class="hlt">Electron</span> <span class="hlt">transport</span> in real time from first-principles.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Morzan, Uriel N; Ramírez, Francisco F; González Lebrero, Mariano C; Scherlis, Damián A</p> <p>2017-01-28</p> <p>While the vast majority of calculations reported on molecular conductance have been based on the static non-equilibrium Green's function formalism combined with density functional theory (DFT), in recent years a few time-dependent approaches to <span class="hlt">transport</span> have started to emerge. Among these, the driven Liouville-von Neumann equation [C. G. Sánchez et al., J. Chem. Phys. 124, 214708 (2006)] is a simple and appealing route relying on a tunable rate parameter, which has been explored in the context of semi-empirical methods. In the present study, we adapt this formulation to a density functional theory framework and analyze its performance. In particular, it is implemented in an efficient all-<span class="hlt">electron</span> DFT code with Gaussian basis functions, suitable for quantum-dynamics simulations of large molecular systems. At variance with the case of the tight-binding calculations reported in the literature, we find that now the initial perturbation to drive the system out of equilibrium plays a fundamental role in the stability of the <span class="hlt">electron</span> dynamics. The equation of motion used in previous tight-binding implementations with massive electrodes has to be modified to produce a stable and unidirectional current during time propagation in time-dependent DFT simulations using much smaller leads. Moreover, we propose a procedure to get rid of the dependence of the current-voltage curves on the rate parameter. This method is employed to obtain the current-voltage characteristic of saturated and unsaturated hydrocarbons of different lengths, with very promising prospects.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/14507427','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/14507427"><span id="translatedtitle">Endosymbiosis and the design of eukaryotic <span class="hlt">electron</span> <span class="hlt">transport</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Berry, Stephan</p> <p>2003-09-30</p> <p>The bioenergetic organelles of eukaryotic cells, mitochondria and chloroplasts, are derived from endosymbiotic bacteria. Their <span class="hlt">electron</span> <span class="hlt">transport</span> chains (ETCs) resemble those of free-living bacteria, but were tailored for energy transformation within the host cell. Parallel evolutionary processes in mitochondria and chloroplasts include reductive as well as expansive events: On one hand, bacterial complexes were lost in eukaryotes with a concomitant loss of metabolic flexibility. On the other hand, new subunits have been added to the remaining bacterial complexes, new complexes have been introduced, and elaborate folding patterns of the thylakoid and mitochondrial inner membranes have emerged. Some bacterial pathways were reinvented independently by eukaryotes, such as parallel routes for quinol oxidation or the use of various anaerobic <span class="hlt">electron</span> acceptors. Multicellular organization and ontogenetic cycles in eukaryotes gave rise to further modifications of the bioenergetic organelles. Besides mitochondria and chloroplasts, eukaryotes have ETCs in other membranes, such as the plasma membrane (PM) redox system, or the cytochrome P450 (CYP) system. These systems have fewer complexes and simpler branching patterns than those in energy-transforming organelles, and they are often adapted to non-bioenergetic functions such as detoxification or cellular defense.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017JChPh.146d4110M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017JChPh.146d4110M"><span id="translatedtitle"><span class="hlt">Electron</span> <span class="hlt">transport</span> in real time from first-principles</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Morzan, Uriel N.; Ramírez, Francisco F.; González Lebrero, Mariano C.; Scherlis, Damián A.</p> <p>2017-01-01</p> <p>While the vast majority of calculations reported on molecular conductance have been based on the static non-equilibrium Green's function formalism combined with density functional theory (DFT), in recent years a few time-dependent approaches to <span class="hlt">transport</span> have started to emerge. Among these, the driven Liouville-von Neumann equation [C. G. Sánchez et al., J. Chem. Phys. 124, 214708 (2006)] is a simple and appealing route relying on a tunable rate parameter, which has been explored in the context of semi-empirical methods. In the present study, we adapt this formulation to a density functional theory framework and analyze its performance. In particular, it is implemented in an efficient all-<span class="hlt">electron</span> DFT code with Gaussian basis functions, suitable for quantum-dynamics simulations of large molecular systems. At variance with the case of the tight-binding calculations reported in the literature, we find that now the initial perturbation to drive the system out of equilibrium plays a fundamental role in the stability of the <span class="hlt">electron</span> dynamics. The equation of motion used in previous tight-binding implementations with massive electrodes has to be modified to produce a stable and unidirectional current during time propagation in time-dependent DFT simulations using much smaller leads. Moreover, we propose a procedure to get rid of the dependence of the current-voltage curves on the rate parameter. This method is employed to obtain the current-voltage characteristic of saturated and unsaturated hydrocarbons of different lengths, with very promising prospects.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/1178203','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/1178203"><span id="translatedtitle">Fast <span class="hlt">electron</span> <span class="hlt">transport</span> in lower-hybrid current drive</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Kupfer, K.; Bers, A.</p> <p>1991-01-01</p> <p>We generalize the quasilinear-Fokker-Planck formulation for lower-hybrid current drive to include the wave induced radial <span class="hlt">transport</span> of fast <span class="hlt">electrons</span>. Toroidal ray tracing shows that the wave fields in the plasma develop a large poloidal component associated with the upshift in k1l and the filling of the "spectral gap". These fields lead to an enhanced radial E x B drift of resonant <span class="hlt">electrons</span>. Two types of radial flows are obtained: an outward convective flow driven by the asymmetry in the poloidal wave spectrum, and a diffusive flow proportional to the width of the poloidal spectrum. Simulations of Alcator C and JT60, show that the radial convection velocity has a broad maximum of nearly 1 m/sec and is independent of the amplitude of fields. In both cases, the radial diffusion is found to be highly localized near the magnetic axis. For JT60, the peak of the diffusion profile can be quite large, nearly 1 m2/sec.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017JPhD...50a5205Z','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017JPhD...50a5205Z"><span id="translatedtitle">Cross-field <span class="hlt">transport</span> of <span class="hlt">electrons</span> at the magnetic throat in an annular plasma reactor</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Zhang, Yunchao; Charles, Christine; Boswell, Rod</p> <p>2017-01-01</p> <p>Cross-field <span class="hlt">transport</span> of <span class="hlt">electrons</span> has been studied at the magnetic throat of the annular Chi-Kung reactor. This annular configuration allows the creation of a low pressure argon plasma with two distinct <span class="hlt">electron</span> heating locations by independently operating a radio-frequency antenna surrounding the outer source tube, or an antenna housed inside the inner source tube. The two antenna cases show opposite variation trends in radial profiles of <span class="hlt">electron</span> energy probability function, <span class="hlt">electron</span> density, plasma potential and <span class="hlt">electron</span> temperature. The momentum and energy <span class="hlt">transport</span> coefficients are obtained from the <span class="hlt">electron</span> energy probability functions, and the related <span class="hlt">electron</span> fluxes follow the path of <span class="hlt">electron</span> cooling across the magnetic throat.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/26512795','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/26512795"><span id="translatedtitle">Detailed Monte Carlo Simulation of <span class="hlt">electron</span> <span class="hlt">transport</span> and <span class="hlt">electron</span> energy loss spectra.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Attarian Shandiz, M; Salvat, F; Gauvin, R</p> <p>2016-11-01</p> <p>A computer program for detailed Monte Carlo simulation of the <span class="hlt">transport</span> of <span class="hlt">electrons</span> with kinetic energies in the range between about 0.1 and about 500 keV in bulk materials and in thin solid films is presented. Elastic scattering is described from differential cross sections calculated by the relativistic (Dirac) partial-wave expansion method with different models of the scattering potential. Inelastic interactions are simulated from an optical-data model based on an empirical optical oscillator strength that combines optical functions of the solid with atomic photoelectric data. The generalized oscillator strength is built from the adopted optical oscillator strength by using an extension algorithm derived from Lindhard's dielectric function for a free-<span class="hlt">electron</span> gas. It is shown that simulated backscattering fractions of <span class="hlt">electron</span> beams from bulk (semi-infinite) specimens are in good agreement with experimental data for beam energies from 0.1 keV up to about 100 keV. Simulations also yield transmitted and backscattered fractions of <span class="hlt">electron</span> beams on thin solid films that agree closely with measurements for different film thicknesses and incidence angles. Simulated most probable deflection angles and depth-dose distributions also agree satisfactorily with measurements. Finally, <span class="hlt">electron</span> energy loss spectra of several elemental solids are simulated and the effects of the beam energy and the foil thickness on the signal to background and signal to noise ratios are investigated. SCANNING 38:475-491, 2016. © 2015 Wiley Periodicals, Inc.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010PhDT........75K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010PhDT........75K"><span id="translatedtitle">Atomistic modeling of <span class="hlt">electronic</span> structure and <span class="hlt">transport</span> in disordered nanostructures</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kharche, Neerav</p> <p></p> <p>As the Si-CMOS technology approaches the end of the International Technology Roadmap for Semiconductors (ITRS), the semiconductor industry faces a formidable challenge to continue the transistor scaling according to Moore's law. To continue the scaling of classical devices, alternative channel materials such as SiGe, carbon nanotubes, nanowires, and III-V based materials are being investigated along with novel 3D device geometries. Researchers are also investigating radically new quantum computing devices, which are expected to perform calculations faster than the existing classical Si-CMOS based structures. Atomic scale disorders such as interface roughness, alloy randomness, non-uniform strain, and dopant fluctuations are routinely present in the experimental realization of such devices. These disorders now play an increasingly important role in determining the <span class="hlt">electronic</span> structure and <span class="hlt">transport</span> properties as device sizes enter the nanometer regime. This work employs the atomistic tight-binding technique, which is ideally suited for modeling systems with local disorders on an atomic scale. High-precision multi-million atom <span class="hlt">electronic</span> structure calculations of (111) Si surface quantum wells and (100) SiGe/Si/SiGe heterostructure quantum wells are performed to investigate the modulation of valley splitting induced by atomic scale disorders. The calculations presented here resolve the existing discrepancies between theoretically predicted and experimentally measured valley splitting, which is an important design parameter in quantum computing devices. Supercell calculations and the zone-unfolding method are used to compute the bandstructures of inhomogeneous nanowires made of AlGaAs and SiGe and their connection with the transmission coefficients computed using non-equilibrium Green's function method is established. A unified picture of alloy nanowires emerges, in which the nanodevice (transmission) and nanomaterials (bandstructure) viewpoints complement each other</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li class="active"><span>15</span></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_15 --> <div id="page_16" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li class="active"><span>16</span></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="301"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015SPIE.9458E..0HA','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015SPIE.9458E..0HA"><span id="translatedtitle">Cyber warfare and <span class="hlt">electronic</span> warfare integration in the operational <span class="hlt">environment</span> of the future: cyber <span class="hlt">electronic</span> warfare</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Askin, Osman; Irmak, Riza; Avsever, Mustafa</p> <p>2015-05-01</p> <p>For the states with advanced technology, effective use of <span class="hlt">electronic</span> warfare and cyber warfare will be the main determining factor of winning a war in the future's operational <span class="hlt">environment</span>. The developed states will be able to finalize the struggles they have entered with a minimum of human casualties and minimum cost thanks to high-tech. Considering the increasing number of world economic problems, the development of human rights and humanitarian law it is easy to understand the importance of minimum cost and minimum loss of human. In this paper, cyber warfare and <span class="hlt">electronic</span> warfare concepts are examined in conjunction with the historical development and the relationship between them is explained. Finally, assessments were carried out about the use of cyber <span class="hlt">electronic</span> warfare in the coming years.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016PlPhR..42..713G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016PlPhR..42..713G"><span id="translatedtitle">Simulation of <span class="hlt">electron</span> beam formation and <span class="hlt">transport</span> in a gas-filled <span class="hlt">electron</span>-optical system with a plasma emitter</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Grishkov, A. A.; Kornilov, S. Yu.; Rempe, N. G.; Shidlovskiy, S. V.; Shklyaev, V. A.</p> <p>2016-07-01</p> <p>The results of computer simulations of the <span class="hlt">electron</span>-optical system of an <span class="hlt">electron</span> gun with a plasma emitter are presented. The simulations are performed using the KOBRA3-INP, XOOPIC, and ANSYS codes. The results describe the <span class="hlt">electron</span> beam formation and <span class="hlt">transport</span>. The <span class="hlt">electron</span> trajectories are analyzed. The mechanisms of gas influence on the energy inhomogeneity of the beam and its current in the regions of beam primary formation, acceleration, and <span class="hlt">transport</span> are described. Recommendations for optimizing the <span class="hlt">electron</span>-optical system with a plasma emitter are presented.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016ApPhL.109o2904O','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016ApPhL.109o2904O"><span id="translatedtitle"><span class="hlt">Electron</span> <span class="hlt">transport</span> and dielectric breakdown in silicon nitride using a charge <span class="hlt">transport</span> model</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ogden, Sean P.; Lu, Toh-Ming; Plawsky, Joel L.</p> <p>2016-10-01</p> <p>Silicon nitride is an important material used in the <span class="hlt">electronics</span> industry. As such, the <span class="hlt">electronic</span> <span class="hlt">transport</span> and reliability of these materials are important to study and understand. We report on a charge <span class="hlt">transport</span> model to predict leakage current and failure trends based on previously published data for a stoichiometric silicon nitride dielectric. Failure occurs when the defect density increases to a critical value of approximately 6 × 1025 traps/m3. The model's parameters are determined using voltage ramp data only, and yet, the model is also able to predict constant voltage stress failure over a time scale ranging from minutes to months. The successful fit of the model to the experimental data validates our assumption that the dominant defect in the dielectric is the Si dangling bond, located approximately 2.2 eV below the conduction band. A comparison with previous SiCOH simulations shows SiN and SiCOH have similar defect-related material properties. It is also speculated that, based on the estimated parameter values of 2.75 eV for the defect formation activation energy, the materials' TDDB wear-out are caused by broken Si-H bonds, resulting in Si dangling bond defects.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.gpo.gov/fdsys/pkg/CFR-2014-title32-vol6/pdf/CFR-2014-title32-vol6-sec2001-23.pdf','CFR2014'); return false;" href="https://www.gpo.gov/fdsys/pkg/CFR-2014-title32-vol6/pdf/CFR-2014-title32-vol6-sec2001-23.pdf"><span id="translatedtitle">32 CFR 2001.23 - Classification marking in the <span class="hlt">electronic</span> <span class="hlt">environment</span>.</span></a></p> <p><a target="_blank" href="http://www.gpo.gov/fdsys/browse/collectionCfr.action?selectedYearFrom=2014&page.go=Go">Code of Federal Regulations, 2014 CFR</a></p> <p></p> <p>2014-07-01</p> <p>... <span class="hlt">environment</span>. 2001.23 Section 2001.23 National Defense Other Regulations Relating to National Defense... <span class="hlt">environment</span>. (a) General. Classified national security information in the <span class="hlt">electronic</span> <span class="hlt">environment</span> shall be: (1... <span class="hlt">electronic</span> <span class="hlt">environment</span> cannot be marked in this manner, a warning shall be applied to alert users that...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.gpo.gov/fdsys/pkg/CFR-2012-title32-vol6/pdf/CFR-2012-title32-vol6-sec2001-23.pdf','CFR2012'); return false;" href="https://www.gpo.gov/fdsys/pkg/CFR-2012-title32-vol6/pdf/CFR-2012-title32-vol6-sec2001-23.pdf"><span id="translatedtitle">32 CFR 2001.23 - Classification marking in the <span class="hlt">electronic</span> <span class="hlt">environment</span>.</span></a></p> <p><a target="_blank" href="http://www.gpo.gov/fdsys/browse/collectionCfr.action?selectedYearFrom=2012&page.go=Go">Code of Federal Regulations, 2012 CFR</a></p> <p></p> <p>2012-07-01</p> <p>... <span class="hlt">environment</span>. 2001.23 Section 2001.23 National Defense Other Regulations Relating to National Defense... <span class="hlt">environment</span>. (a) General. Classified national security information in the <span class="hlt">electronic</span> <span class="hlt">environment</span> shall be: (1... <span class="hlt">electronic</span> <span class="hlt">environment</span> cannot be marked in this manner, a warning shall be applied to alert users that...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/24061333','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/24061333"><span id="translatedtitle"><span class="hlt">Electron</span> <span class="hlt">transport</span> through 5-substituted pyrimidines in DNA: <span class="hlt">electron</span> affinities of uracil and cytosine derivatives differently affect the apparent efficiencies.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Ito, Takeo; Kurihara, Ryohsuke; Utsumi, Nihiro; Hamaguchi, Yuta; Tanabe, Kazuhito; Nishimoto, Sei-ichi</p> <p>2013-11-11</p> <p>We investigated excess <span class="hlt">electron</span> <span class="hlt">transport</span> (EET) in DNA containing cytosine derivatives. By arranging the derivatives according to their <span class="hlt">electron</span> affinities, the apparent EET efficiency was successfully regulated. Unexpectedly, however, providing gradients of <span class="hlt">electron</span> affinity by inserting 5-fluorocytosine did not always enhance EET.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/5161610','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/5161610"><span id="translatedtitle">Mass transfer and <span class="hlt">transport</span> in a geologic <span class="hlt">environment</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Chambre, P.L.; Pigford, T.H.; Lee, W.W.L.; Ahn, J.; Kajiwara, S.; Kim, C.L.; Kimura, H.; Lung, H.; Williams, W.J.; Zavoshy, S.J.</p> <p>1985-04-01</p> <p>This report is in a continuing series of reports that present analytic solutions for the dissolution and hydrogeologic <span class="hlt">transport</span> of radionuclides from geologic repositories of nuclear waste. Previous reports have dealt mainly with radionuclide <span class="hlt">transport</span> in the far-field, away from the effects of the repository. In the present report, the emphasis is on near-field processes, the transfer and <span class="hlt">transport</span> of radionuclides in the vicinity of the waste packages. The primary tool used in these analyses is mass transfer theory from chemical engineering. The thrust of our work is to develop methods for predicting the performance of geologic repositories. The subjects treated in the present report are: radionuclide <span class="hlt">transport</span> from a spherical-equivalent waste form through a backfill; analysis of radionuclide <span class="hlt">transport</span> through a backfill using a non-linear sorption isotherm; radionuclide <span class="hlt">transport</span> from a prolate spheroid-equivalent waste form with a backfill; radionuclide <span class="hlt">transport</span> from a spherical-equivalent waste form through a backfill, where the solubility, diffusivity and retardation coefficients are temperature dependent; a coupled near-field, far-field analysis where dissolution and migration rates are temperature dependent; <span class="hlt">transport</span> of radionuclides from a point source in a three-dimensional flow field; and a general solution for the <span class="hlt">transport</span> of radioactive chains in geologic media. There are several important results from the numerical evaluations. First, radioactive decay, higher sorption in the rock and the backfill steepens the gradient for mass transfer, and lead to higher dissolution rates. This is contrary to what was expected by some other workers, but is shown clearly in the analytical solutions. Second, the backfill serves to provide sorption sites so that there is a delay in the arrival of radionuclides in the rock, although this effect is not so important for the steady-state <span class="hlt">transport</span> of long-lived radionuclides.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/1287449','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/1287449"><span id="translatedtitle"><span class="hlt">Electron</span> <span class="hlt">Transport</span> Modeling of Molecular Nanoscale Bridges Used in Energy Conversion Schemes</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Dunietz, Barry D.</p> <p>2016-08-09</p> <p>The goal of the research program is to reliably describe <span class="hlt">electron</span> <span class="hlt">transport</span> and transfer processes at the molecular level. Such insight is essential for improving molecular applications of solar and thermal energy conversion. We develop <span class="hlt">electronic</span> structure models to study (1) photoinduced <span class="hlt">electron</span> transfer and <span class="hlt">transport</span> processes in organic semiconducting materials, and (2) charge and heat <span class="hlt">transport</span> through molecular bridges. We seek fundamental understanding of key processes, which lead to design new experiments and ultimately to achieve systems with improved properties.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013CoTPh..59..121B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013CoTPh..59..121B"><span id="translatedtitle">Simulation Study of the <span class="hlt">Electron</span> and Hole <span class="hlt">Transport</span> in a CNTFET</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Bahari, A.; Amiri, M.</p> <p>2013-01-01</p> <p>In this work we have investigated <span class="hlt">electron</span> and hole <span class="hlt">transport</span> through zig zag carbon nanotubes by solving Boltzmann <span class="hlt">Transport</span> Equation (BTE). We find that the mobility of <span class="hlt">electrons</span> is rather greater than holes. Carbo nanotubes with longer diameter can carry higher current. Normally, <span class="hlt">transport</span> of <span class="hlt">electrons</span> (or holes) is dominated by scattering events, which relax the carrier momentum in an effort to bring the conducting material to equilibrium.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013PhDT.......276M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013PhDT.......276M"><span id="translatedtitle"><span class="hlt">Transport</span> of Zinc Oxide Nanoparticles in a Simulated Gastric <span class="hlt">Environment</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Mayfield, Ryan T.</p> <p></p> <p>Recent years have seen a growing interest in the use of many types of nano sized materials in the consumer sector. Potential uses include encapsulation of nutrients, providing antimicrobial activity, altering texture, or changing bioavailability of nutrients. Engineered nanoparticles (ENP) possess properties that are different than larger particles made of the same constituents. Properties such as solubility, aggregation state, and toxicity can all be changed as a function of size. The gastric <span class="hlt">environment</span> is an important area for study of engineered nanoparticles because of the varied physical, chemical, and enzymatic processes that are prevalent there. These all have the potential to alter those properties of ENP that make them different from their bulk counterparts. The Human Gastric Simulator (HGS) is an advanced in vitro model that can be used to study many facets of digestion. The HGS consists of a plastic lining that acts as the stomach cavity with two sets of U-shaped arms on belts that provide the physical forces needed to replicate peristalsis. Altering the position of the arms or changing the speed of the motor which powers them allows one to tightly hone and replicate varied digestive conditions. Gastric juice, consisting of salts, enzymes, and acid levels which replicate physiological conditions, is introduced to the cavity at a controllable rate. The release of digested food from the lumen of simulated stomach is controlled by a peristaltic pump. The goal of the HGS is to accurately and repeatedly simulate human digestion. This study focused on introducing foods spiked with zinc oxide ENP and bulk zinc oxide into the HGS and then monitoring how the concentration of each changed at two locations in the HGS over a two hour period. The two locations chosen were the highest point in the lumen of the stomach, which represented the fundus, and a point just beyond the equivalent of the pylorus, which represented the antrum of the stomach. These points were</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20060051442&hterms=extreme+running&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3Dextreme%2Brunning','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20060051442&hterms=extreme+running&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3Dextreme%2Brunning"><span id="translatedtitle">Reconfiguration of Analog <span class="hlt">Electronics</span> for Extreme <span class="hlt">Environments</span>: Problem or Solution?</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Stoica, Adrian; Zebulum, Ricardo; Keymeulen, Didier; Guo, Xin</p> <p>2005-01-01</p> <p>This paper argues in favor of adaptive reconfiguration as a technique to expand the operational envelope of analog <span class="hlt">electronics</span> for extreme <span class="hlt">environments</span> (EE). In addition to hardening-by-process and hardening-by-design, "hardening-by-reconfiguration", when applicable, could be used to mitigate drifts, degradation, or damage on <span class="hlt">electronic</span> devices (chips) in EE, by using re-configurable devices and an adaptive self-reconfiguration of their circuit topology. Conventional circuit design exploits device characteristics within a certain temperature/radiation range; when that is exceeded, the circuit function degrades. On a reconfigurable device, although component parameters change in EE, as long as devices still operate, albeit degraded, a new circuit design, suitable for new parameter values, may be mapped into the reconfigurable structure to recover the initial circuit function. Partly degraded resources are still used, while completely damaged resources are bypassed. Designs suitable for various environmental conditions can be determined prior to operation or can be determined in-situ, by adaptive reconfiguration algorithms running on built-in digital controllers. Laboratory demonstrations of this technique were performed by JPL in several independent experiments in which bulk CMOS reconfigurable devices were exposed to, and degraded by, low temperatures (approx. 196 C), high temperatures (approx.300 C) or radiation (300kRad TID), and then recovered by adaptive reconfiguration using evolutionary search algorithms. Taking this technology from Technology Readiness Level (TRL) 3 to TRL 5 is the target of a current NASA project.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/23176467','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/23176467"><span id="translatedtitle">A long way to the electrode: how do Geobacter cells <span class="hlt">transport</span> their <span class="hlt">electrons</span>?</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Bonanni, Pablo Sebastián; Schrott, Germán David; Busalmen, Juan Pablo</p> <p>2012-12-01</p> <p>The mechanism of <span class="hlt">electron</span> <span class="hlt">transport</span> in Geobacter sulfurreducens biofilms is a topic under intense study and debate. Although some proteins were found to be essential for current production, the specific role that each one plays in <span class="hlt">electron</span> <span class="hlt">transport</span> to the electrode remains to be elucidated and a consensus on the mechanism of <span class="hlt">electron</span> <span class="hlt">transport</span> has not been reached. In the present paper, to understand the state of the art in the topic, <span class="hlt">electron</span> <span class="hlt">transport</span> from inside of the cell to the electrode in Geobacter sulfurreducens biofilms is analysed, reviewing genetic studies, biofilm conductivity assays and electrochemical and spectro-electrochemical experiments. Furthermore, crucial data still required to achieve a deeper understanding are highlighted.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://eric.ed.gov/?q=vehicular+AND+pollution&id=ED147590','ERIC'); return false;" href="http://eric.ed.gov/?q=vehicular+AND+pollution&id=ED147590"><span id="translatedtitle"><span class="hlt">Transportation</span> and the <span class="hlt">Environment</span> in Harmony: Mini-Units and Learning Activities for Grades 9 through 12.</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Finn, Peter; And Others</p> <p></p> <p>One of a series of eleven curriculum manuals which cover the four <span class="hlt">transportation</span> topics of public <span class="hlt">transportation</span>, <span class="hlt">transportation</span> and the <span class="hlt">environment</span>, <span class="hlt">transportation</span> safety, and bicycles for elementary, secondary, and adult levels, this manual covers the <span class="hlt">transportation</span> and the <span class="hlt">environment</span> topic for grades 9-12. It contains forty-four learning…</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://eric.ed.gov/?q=vehicular+AND+pollution&id=ED147589','ERIC'); return false;" href="http://eric.ed.gov/?q=vehicular+AND+pollution&id=ED147589"><span id="translatedtitle"><span class="hlt">Transportation</span> and the <span class="hlt">Environment</span> in Harmony: Mini-Units and Learning Activities for Grades 6 through 9.</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Finn, Peter; And Others</p> <p></p> <p>One of a series of eleven curriculum manuals which cover the four <span class="hlt">transportation</span> topics of public <span class="hlt">transportation</span>, <span class="hlt">transportation</span> and the <span class="hlt">environment</span>, <span class="hlt">transportation</span> safety, and bicycles for elementary, secondary, and adult levels, this manual covers the <span class="hlt">transportation</span> and the <span class="hlt">environment</span> topic for grades 6-9. It contains thirty-nine learning…</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014JAP...115t3714A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014JAP...115t3714A"><span id="translatedtitle">Local atomic order, <span class="hlt">electronic</span> structure and <span class="hlt">electron</span> <span class="hlt">transport</span> properties of Cu-Zr metallic glasses</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Antonowicz, J.; Pietnoczka, A.; Pekała, K.; Latuch, J.; Evangelakis, G. A.</p> <p>2014-05-01</p> <p>We studied atomic and <span class="hlt">electronic</span> structures of binary Cu-Zr metallic glasses (MGs) using combined experimental and computational methods including X-ray absorption fine structure spectroscopy, electrical resistivity, thermoelectric power (TEP) measurements, molecular dynamics (MD) simulations, and ab-initio calculations. The results of MD simulations and extended X-ray absorption fine structure analysis indicate that atomic order of Cu-Zr MGs and can be described in terms of interpenetrating icosahedral-like clusters involving five-fold symmetry. MD configurations were used as an input for calculations of theoretical <span class="hlt">electronic</span> density of states (DOS) functions which exhibits good agreement with the experimental X-ray absorption near-edge spectra. We found no indication of minimum of DOS at Fermi energy predicted by Mott's nearly free <span class="hlt">electron</span> (NFE) model for glass-forming alloys. The theoretical DOS was subsequently used to test Mott's model describing the temperature variation of electrical resistivity and thermoelectric power of transition metal-based MGs. We demonstrate that the measured temperature variations of electrical resistivity and TEP remain in a contradiction with this model. On the other hand, the experimental temperature dependence of electrical resistivity can be explained by incipient localization of conduction <span class="hlt">electrons</span>. It is shown that weak localization model works up to relatively high temperatures when localization is destroyed by phonons. Our results indicate that <span class="hlt">electron</span> <span class="hlt">transport</span> properties of Cu-Zr MGs are dominated by localization effects rather than by <span class="hlt">electronic</span> structure. We suggest that NFE model fails to explain a relatively high glass-forming ability of binary Cu-Zr alloys.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/22304308','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/22304308"><span id="translatedtitle">Local atomic order, <span class="hlt">electronic</span> structure and <span class="hlt">electron</span> <span class="hlt">transport</span> properties of Cu-Zr metallic glasses</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Antonowicz, J. Pietnoczka, A.; Pękała, K.; Latuch, J.; Evangelakis, G. A.</p> <p>2014-05-28</p> <p>We studied atomic and <span class="hlt">electronic</span> structures of binary Cu-Zr metallic glasses (MGs) using combined experimental and computational methods including X-ray absorption fine structure spectroscopy, electrical resistivity, thermoelectric power (TEP) measurements, molecular dynamics (MD) simulations, and ab-initio calculations. The results of MD simulations and extended X-ray absorption fine structure analysis indicate that atomic order of Cu-Zr MGs and can be described in terms of interpenetrating icosahedral-like clusters involving five-fold symmetry. MD configurations were used as an input for calculations of theoretical <span class="hlt">electronic</span> density of states (DOS) functions which exhibits good agreement with the experimental X-ray absorption near-edge spectra. We found no indication of minimum of DOS at Fermi energy predicted by Mott's nearly free <span class="hlt">electron</span> (NFE) model for glass-forming alloys. The theoretical DOS was subsequently used to test Mott's model describing the temperature variation of electrical resistivity and thermoelectric power of transition metal-based MGs. We demonstrate that the measured temperature variations of electrical resistivity and TEP remain in a contradiction with this model. On the other hand, the experimental temperature dependence of electrical resistivity can be explained by incipient localization of conduction <span class="hlt">electrons</span>. It is shown that weak localization model works up to relatively high temperatures when localization is destroyed by phonons. Our results indicate that <span class="hlt">electron</span> <span class="hlt">transport</span> properties of Cu-Zr MGs are dominated by localization effects rather than by <span class="hlt">electronic</span> structure. We suggest that NFE model fails to explain a relatively high glass-forming ability of binary Cu-Zr alloys.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20050169213','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20050169213"><span id="translatedtitle">Energetic <span class="hlt">Electron</span> <span class="hlt">Transport</span> in the Inner Magnetosphere During Geomagnetic Storms and Substorms</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>McKenzie, D. L.; Anderson, P. C.</p> <p>2005-01-01</p> <p>We propose to examine the relationship of geomagnetic storms and substorms and the <span class="hlt">transport</span> of energetic particles in the inner magnetosphere using measurements of the auroral X-ray emissions by PIXIE. PIXIE provides a global view of the auroral oval for the extended periods of time required to study stormtime phenomena. Its unique energy response and global view allow separation of stormtime particle <span class="hlt">transport</span> driven by strong magnetospheric electric fields from substorm particle <span class="hlt">transport</span> driven by magnetic-field dipolarization and subsequent particle injection. The relative importance of substorms in releasing stored magnetospheric energy during storms and injecting particles into the inner magnetosphere and the ring current is currently hotly debated. The distribution of particles in the inner magnetosphere is often inferred from measurements of the precipitating auroral particles. Thus, the global distributions of the characteristics of energetic precipitating particles during storms and substorms are extremely important inputs to any description or model of the geospace <span class="hlt">environment</span> and the Sun-Earth connection. We propose to use PIXIE observations and modeling of the <span class="hlt">transport</span> of energetic <span class="hlt">electrons</span> to examine the relationship between storms and substorms.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016JPS...320..343H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016JPS...320..343H"><span id="translatedtitle">Quantification of ionic <span class="hlt">transport</span> within thermally-activated batteries using <span class="hlt">electron</span> probe micro-analysis</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Humplik, Thomas; Stirrup, Emily K.; Grillet, Anne M.; Grant, Richard P.; Allen, Ashley N.; Wesolowski, Daniel E.; Roberts, Christine C.</p> <p>2016-07-01</p> <p>The transient <span class="hlt">transport</span> of electrolytes in thermally-activated batteries is studied using <span class="hlt">electron</span> probe micro-analysis (EPMA), demonstrating the robust capability of EPMA as a useful tool for studying and quantifying mass <span class="hlt">transport</span> within porous materials, particularly in difficult <span class="hlt">environments</span> where classical flow measurements are challenging. By tracking the mobility of bromine and potassium ions from the electrolyte stored within the separator into the lithium silicon anode and iron disulfide cathode, we are able to quantify the <span class="hlt">transport</span> mechanisms and physical properties of the electrodes including permeability and tortuosity. Due to the micron to submicron scale porous structure of the initially dry anode, a fast capillary pressure driven flow is observed into the anode from which we are able to set a lower bound on the permeability of 10-1 mDarcy. The <span class="hlt">transport</span> into the cathode is diffusion-limited because the cathode originally contained some electrolyte before activation. Using a transient one-dimensional diffusion model, we estimate the tortuosity of the cathode electrode to be 2.8 ± 0.8.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016Nanot..27H5503P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016Nanot..27H5503P"><span id="translatedtitle">Surface trap mediated <span class="hlt">electronic</span> <span class="hlt">transport</span> in biofunctionalized silicon nanowires</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Puppo, F.; Traversa, F. L.; Di Ventra, M.; De Micheli, G.; Carrara, S.</p> <p>2016-08-01</p> <p>Silicon nanowires (SiNWs), fabricated via a top-down approach and then functionalized with biological probes, are used for electrically-based sensing of breast tumor markers. The SiNWs, featuring memristive-like behavior in bare conditions, show, in the presence of biomarkers, modified hysteresis and, more importantly, a voltage memory component, namely a voltage gap. The voltage gap is demonstrated to be a novel and powerful parameter of detection thanks to its high-resolution dependence on charges in proximity of the wire. This unique approach of sensing has never been studied and adopted before. Here, we propose a physical model of the surface <span class="hlt">electronic</span> <span class="hlt">transport</span> in Schottky barrier SiNW biosensors, aiming at reproducing and understanding the voltage gap based behavior. The implemented model describes well the experimental I-V characteristics of the device. It also links the modification of the voltage gap to the changing concentration of antigens by showing the decrease of this parameter in response to increasing concentrations of the molecules that are detected with femtomolar resolution in real human samples. Both experiments and simulations highlight the predominant role of the dynamic recombination of the nanowire surface states, with the incoming external charges from bio-species, in the appearance and modification of the voltage gap. Finally, thanks to its compactness, and strict correlation with the physics of the nanodevice, this model can be used to describe and predict the I-V characteristics in other nanostructured devices, for different than antibody-based sensing as well as <span class="hlt">electronic</span> applications.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/22341856','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/22341856"><span id="translatedtitle">Study of <span class="hlt">electronic</span> <span class="hlt">transport</span> in gamma ray exposed nanowires</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Gehlawat, Devender Chauhan, R.P.</p> <p>2014-01-01</p> <p>Graphical abstract: A sharp decline in the I–V characteristics of Cu (and Cd) nanowires was experimentally observed after the gamma ray exposure of nanowires. Irradiation induced transformations in the granular properties and the resonance state of electron–phonon coupling beyond a particular value of external field may be accountable for observed shape of I–V characteristics in gamma ray exposed nanowires. - Highlights: • Cu and Cd nanowires were synthesized by technique of electrodeposition in templates. • The nanowires were exposed to different doses of gamma ray photons. • A sharp decline in the current in I–V characteristics (IVC) was observed. • Structural deviation in terms of granular orientations was also analysed. • The electron–phonon coupling may be responsible for observed sharp decline in IVC. - Abstract: One dimensional nanostructures provide the most restricted and narrow channel for the <span class="hlt">transport</span> of charge carriers and therefore 1D structures preserve their significance from the viewpoint of <span class="hlt">electronic</span> devices. The net radiation effect on nanomaterials is expected to be more (due to their increased reactivity and lesser bulk volume) than their bulk counterparts. Radiation often modifies the structure and simultaneously the other physical properties of materials. In this manner, the irradiation phenomenon could be counted as a strong criterion to induce changes in the structural and electrical properties of nanowires. We have studied the effect of gamma rays on the <span class="hlt">electronic</span> flow through Cu and Cd nanowires by plotting their I–V characteristics (IVC). The IVC of gamma ray exposed nanowires was found to be a combination of the linear and nonlinear regions and a decreasing pattern in the electrical conductivity (calculated from the linear portion of IVC) was observed as we increased the dose of gamma rays.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li class="active"><span>16</span></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_16 --> <div id="page_17" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li class="active"><span>17</span></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="321"> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/40204621','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/40204621"><span id="translatedtitle">Experimental Characterization of the <span class="hlt">Electron</span> Heat <span class="hlt">Transport</span> in Low-Density ASDEX Upgrade Plasmas</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Ryter, F.; Imbeaux, F.; Leuterer, F.; Fahrbach, H.-U.; Suttrop, W.; ASDEX Upgrade Team</p> <p>2001-06-11</p> <p>The <span class="hlt">electron</span> heat <span class="hlt">transport</span> is investigated in ASDEX Upgrade conventional L -mode plasmas with pure <span class="hlt">electron</span> heating provided by <span class="hlt">electron</span>-cyclotron heating (ECH) at low density. Under these conditions, steady-state and ECH modulation experiments indicate without ambiguity that <span class="hlt">electron</span> heat <span class="hlt">transport</span> exhibits a clear threshold in {nabla}T{sub e}/T{sub e} and also suggest that it has a gyro-Bohm character.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/pages/biblio/1185679-defect-mediated-transport-electronic-irradiation-effect-individual-domains-cvd-grown-monolayer-mos2','SCIGOV-DOEP'); return false;" href="https://www.osti.gov/pages/biblio/1185679-defect-mediated-transport-electronic-irradiation-effect-individual-domains-cvd-grown-monolayer-mos2"><span id="translatedtitle">Defect-mediated <span class="hlt">transport</span> and <span class="hlt">electronic</span> irradiation effect in individual domains of CVD-grown monolayer MoS2</span></a></p> <p><a target="_blank" href="http://www.osti.gov/pages">DOE PAGES</a></p> <p>Durand, Corentin; Zhang, Xiaoguang; Fowlkes, Jason; ...</p> <p>2015-01-16</p> <p>We study the electrical <span class="hlt">transport</span> properties of atomically thin individual crystalline grains of MoS2 with four-probe scanning tunneling microscopy. The monolayer MoS2 domains are synthesized by chemical vapor deposition on SiO2/Si substrate. Temperature dependent measurements on conductance and mobility show that <span class="hlt">transport</span> is dominated by an <span class="hlt">electron</span> charge trapping and thermal release process with very low carrier density and mobility. The effects of <span class="hlt">electronic</span> irradiation are examined by exposing the film to <span class="hlt">electron</span> beam in the scanning <span class="hlt">electron</span> microscope in an ultrahigh vacuum <span class="hlt">environment</span>. The irradiation process is found to significantly affect the mobility and the carrier density of themore » material, with the conductance showing a peculiar time-dependent relaxation behavior. It is suggested that the presence of defects in active MoS2 layer and dielectric layer create charge trapping sites, and a multiple trapping and thermal release process dictates the <span class="hlt">transport</span> and mobility characteristics. The <span class="hlt">electron</span> beam irradiation promotes the formation of defects and impact the electrical properties of MoS2. Finally, our study reveals the important roles of defects and the <span class="hlt">electron</span> beam irradiation effects in the <span class="hlt">electronic</span> properties of atomic layers of MoS2.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016APS..DPPPI3002M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016APS..DPPPI3002M"><span id="translatedtitle"><span class="hlt">Electron</span> turbulence and <span class="hlt">transport</span> in large magnetic islands</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Morton, Lucas</p> <p>2016-10-01</p> <p>Magnetic islands, observed in both reversed-field pinches (RFPs) and tokamaks, often display unexpected turbulence and <span class="hlt">transport</span> characteristics. For the first time in an RFP, the high repetition rate Thomson scattering diagnostic on MST has captured a 2D image of the rotating <span class="hlt">electron</span> temperature structure of a magnetic island in a single discharge. MHD modeling using edge magnetic signals implies a 16 cm wide m,n =1,6 tearing mode island which completely overlaps a 5.5 cm n =7 island (12 cm between island centers). The 3D field is partially chaotic, but still reflective of the n =6 island structure. The measured temperature structure matches the shape and location of the n =6 partially chaotic (or `remnant') island. Contrary to the usual assumption that islands have flat internal temperature, the <span class="hlt">electron</span> temperature is peaked inside the remnant magnetic island due to ohmic heating. The temperature peaking implies a local effective perpendicular conductivity 10-40 m2/s inside the remnant island. This agrees quantitatively with an effective perpendicular conductivity of 16 m2/s estimated using the magnetic diffusion coefficient (evaluated at the <span class="hlt">electron</span> mean free path) calculated from the modeled chaotic field. Statistical analysis of measurement ensembles with lower time resolution implies that remnant island heating is common in MST discharges. To investigate the role of turbulence near a magnetic island, the 2D structure of long-wavelength density turbulence has been mapped around a large applied static m,n =2,1 L-mode island in the DIII-D tokamak. The turbulence exhibits intriguing spatial structure. Fluctuations are enhanced several-fold (compared to the no-island case) on the inboard side of the X-point, but not on the outboard side of the X-point and are also reduced near the O-point. This work is supported by the NSF and US DOE under DE-FC02-04ER54698, and DE-FG02-89ER53296.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5381704','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5381704"><span id="translatedtitle"><span class="hlt">Electronic</span> <span class="hlt">transport</span> in two-dimensional high dielectric constant nanosystems</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Ortuño, M.; Somoza, A. M.; Vinokur, V. M.; Baturina, T. I.</p> <p>2015-01-01</p> <p>There has been remarkable recent progress in engineering high-dielectric constant two dimensional (2D) materials, which are being actively pursued for applications in nanoelectronics in capacitor and memory devices, energy storage, and high-frequency modulation in communication devices. Yet many of the unique properties of these systems are poorly understood and remain unexplored. Here we report a numerical study of hopping conductivity of the lateral network of capacitors, which models two-dimensional insulators, and demonstrate that 2D long-range Coulomb interactions lead to peculiar size effects. We find that the characteristic energy governing <span class="hlt">electronic</span> <span class="hlt">transport</span> scales logarithmically with either system size or electrostatic screening length depending on which one is shorter. Our results are relevant well beyond their immediate context, explaining, for example, recent experimental observations of logarithmic size dependence of electric conductivity of thin superconducting films in the critical vicinity of superconductor-insulator transition where a giant dielectric constant develops. Our findings mark a radical departure from the orthodox view of conductivity in 2D systems as a local characteristic of materials and establish its macroscopic global character as a generic property of high-dielectric constant 2D nanomaterials. PMID:25860804</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/pages/biblio/1200859-electronic-transport-two-dimensional-high-dielectric-constant-nanosystems','SCIGOV-DOEP'); return false;" href="https://www.osti.gov/pages/biblio/1200859-electronic-transport-two-dimensional-high-dielectric-constant-nanosystems"><span id="translatedtitle"><span class="hlt">Electronic</span> <span class="hlt">transport</span> in two-dimensional high dielectric constant nanosystems</span></a></p> <p><a target="_blank" href="http://www.osti.gov/pages">DOE PAGES</a></p> <p>Ortuño, M.; Somoza, A. M.; Vinokur, V. M.; ...</p> <p>2015-04-10</p> <p>There has been remarkable recent progress in engineering high-dielectric constant two dimensional (2D) materials, which are being actively pursued for applications in nanoelectronics in capacitor and memory devices, energy storage, and high-frequency modulation in communication devices. Yet many of the unique properties of these systems are poorly understood and remain unexplored. Here we report a numerical study of hopping conductivity of the lateral network of capacitors, which models two-dimensional insulators, and demonstrate that 2D long-range Coulomb interactions lead to peculiar size effects. We find that the characteristic energy governing <span class="hlt">electronic</span> <span class="hlt">transport</span> scales logarithmically with either system size or electrostatic screeningmore » length depending on which one is shorter. Our results are relevant well beyond their immediate context, explaining, for example, recent experimental observations of logarithmic size dependence of electric conductivity of thin superconducting films in the critical vicinity of superconductor-insulator transition where a giant dielectric constant develops. Our findings mark a radical departure from the orthodox view of conductivity in 2D systems as a local characteristic of materials and establish its macroscopic global character as a generic property of high-dielectric constant 2D nanomaterials.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/1200859','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/1200859"><span id="translatedtitle"><span class="hlt">Electronic</span> <span class="hlt">transport</span> in two-dimensional high dielectric constant nanosystems</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Ortuño, M.; Somoza, A. M.; Vinokur, V. M.; Baturina, T. I.</p> <p>2015-04-10</p> <p>There has been remarkable recent progress in engineering high-dielectric constant two dimensional (2D) materials, which are being actively pursued for applications in nanoelectronics in capacitor and memory devices, energy storage, and high-frequency modulation in communication devices. Yet many of the unique properties of these systems are poorly understood and remain unexplored. Here we report a numerical study of hopping conductivity of the lateral network of capacitors, which models two-dimensional insulators, and demonstrate that 2D long-range Coulomb interactions lead to peculiar size effects. We find that the characteristic energy governing <span class="hlt">electronic</span> <span class="hlt">transport</span> scales logarithmically with either system size or electrostatic screening length depending on which one is shorter. Our results are relevant well beyond their immediate context, explaining, for example, recent experimental observations of logarithmic size dependence of electric conductivity of thin superconducting films in the critical vicinity of superconductor-insulator transition where a giant dielectric constant develops. Our findings mark a radical departure from the orthodox view of conductivity in 2D systems as a local characteristic of materials and establish its macroscopic global character as a generic property of high-dielectric constant 2D nanomaterials.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/6067021','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/6067021"><span id="translatedtitle">Considerations of beta and <span class="hlt">electron</span> <span class="hlt">transport</span> in internal dose calculations</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Bolch, W.E.; Poston, J.W. Sr. . Dept. of Nuclear Engineering)</p> <p>1990-12-01</p> <p>Ionizing radiation has broad uses in modern science and medicine. These uses often require the calculation of energy deposition in the irradiated media and, usually, the medium of interest is the human body. Energy deposition from radioactive sources within the human body and the effects of such deposition are considered in the field of internal dosimetry. In July of 1988, a three-year research project was initiated by the Nuclear Engineering Department at Texas A M University under the sponsorship of the US Department of Energy. The main thrust of the research was to consider, for the first time, the detailed spatial <span class="hlt">transport</span> of <span class="hlt">electron</span> and beta particles in the estimation of average organ doses under the Medical Internal Radiation Dose (MIRD) schema. At the present time (December of 1990), research activities are continuing within five areas. Several are new initiatives begun within the second or third year of the current contract period. They include: (1) development of small-scale dosimetry; (2) development of a differential volume phantom; (3) development of a dosimetric bone model; (4) assessment of the new ICRP lung model; and (5) studies into the mechanisms of DNA damage. A progress report is given for each of these tasks within the Comprehensive Report. In each use, preliminary results are very encouraging and plans for further research are detailed within this document. 22 refs., 13 figs., 1 tab.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/6067078','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/6067078"><span id="translatedtitle">Considerations of beta and <span class="hlt">electron</span> <span class="hlt">transport</span> in internal dose calculations</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Bolch, W.E.; Poston, J.W. Sr.</p> <p>1990-12-01</p> <p>Ionizing radiation has broad uses in modern science and medicine. These uses often require the calculation of energy deposition in the irradiated media and, usually, the medium of interest is the human body. Energy deposition from radioactive sources within the human body and the effects of such deposition are considered in the field of internal dosimetry. In July of 1988, a three-year research project was initiated by the Nuclear Engineering Department at Texas A M University under the sponsorship of the US Department of Energy. The main thrust of the research was to consider, for the first time, the detailed spatial <span class="hlt">transport</span> of <span class="hlt">electron</span> and beta particles in the estimation of average organ doses under the Medical Internal Radiation Dose (MIRD) schema. At the present time (December of 1990), research activities are continuing within five areas. Several are new initiatives begun within the second or third year of the current contract period. They include: (1) development of small-scale dosimetry; (2) development of a differential volume phantom; (3) development of a dosimetric bone model; (4) assessment of the new ICRP lung model; and (5) studies into the mechanisms of DNA damage. A progress report is given for each of these tasks within the Comprehensive Report. In each case, preliminary results are very encouraging and plans for further research are detailed within this document.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4891735','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4891735"><span id="translatedtitle">Defect engineering of the <span class="hlt">electronic</span> <span class="hlt">transport</span> through cuprous oxide interlayers</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Fadlallah, Mohamed M.; Eckern, Ulrich; Schwingenschlögl, Udo</p> <p>2016-01-01</p> <p>The <span class="hlt">electronic</span> <span class="hlt">transport</span> through Au–(Cu2O)n–Au junctions is investigated using first-principles calculations and the nonequilibrium Green’s function method. The effect of varying the thickness (i.e., n) is studied as well as that of point defects and anion substitution. For all Cu2O thicknesses the conductance is more enhanced by bulk-like (in contrast to near-interface) defects, with the exception of O vacancies and Cl substitutional defects. A similar transmission behavior results from Cu deficiency and N substitution, as well as from Cl substitution and N interstitials for thick Cu2O junctions. In agreement with recent experimental observations, it is found that N and Cl doping enhances the conductance. A Frenkel defect, i.e., a superposition of an O interstitial and O substitutional defect, leads to a remarkably high conductance. From the analysis of the defect formation energies, Cu vacancies are found to be particularly stable, in agreement with earlier experimental and theoretical work. PMID:27256905</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017PhRvB..95h5303W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017PhRvB..95h5303W"><span id="translatedtitle">Comparative investigation of <span class="hlt">electronic</span> <span class="hlt">transport</span> across three-dimensional nanojunctions</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Wang, Yun-Peng; Zhang, X.-G.; Fry, J. N.; Cheng, Hai-Ping</p> <p>2017-02-01</p> <p>We show the thickness-dependent transition from metallic conduction to tunneling in three-dimensional (3D) Ag/Si/Ag nanojunctions through layer-by-layer <span class="hlt">electronic</span> structure and quantum <span class="hlt">transport</span> calculations. The transmission coefficients are calculated quantum mechanically within the framework of density functional theory in conjunction with nonequilibrium Green's function techniques. Thin junctions show nearly metallic character with no energy gap opening in Si layers due to the metal-induced interface states, and the transmission is independent of the stacking order of Si layers. An energy gap reemerges for Si layers deeply buried within thick junction, and the decay rate of transmission in this insulating region depends on the stacking order. Complex band analysis indicates that the decay of transmission is not determined by a single exponential constant but also depends on the available number of evanescent states. Calculating the electric resistance from the transmission coefficient requires a 3D generalization of the Landauer formula, which is not unique. We examine two approaches, the Landauer-Büttiker formula, with and without subtraction of the Sharvin resistance, and a semiclassical Boltzmann equation with boundary conditions defined by the transmission coefficients at the junction. We identify an empirical upper limit of ˜0.05 per channel in the transmission coefficient, below which the Landauer-Büttiker formula without the Sharvin resistance correction remains a good approximation. In the high transmission limit, the Landauer-Büttiker formula with Sharvin correction and the semiclassical Boltzmann method reach fair agreement.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016NatSR...627049F','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016NatSR...627049F"><span id="translatedtitle">Defect engineering of the <span class="hlt">electronic</span> <span class="hlt">transport</span> through cuprous oxide interlayers</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Fadlallah, Mohamed M.; Eckern, Ulrich; Schwingenschlögl, Udo</p> <p>2016-06-01</p> <p>The <span class="hlt">electronic</span> <span class="hlt">transport</span> through Au–(Cu2O)n–Au junctions is investigated using first-principles calculations and the nonequilibrium Green’s function method. The effect of varying the thickness (i.e., n) is studied as well as that of point defects and anion substitution. For all Cu2O thicknesses the conductance is more enhanced by bulk-like (in contrast to near-interface) defects, with the exception of O vacancies and Cl substitutional defects. A similar transmission behavior results from Cu deficiency and N substitution, as well as from Cl substitution and N interstitials for thick Cu2O junctions. In agreement with recent experimental observations, it is found that N and Cl doping enhances the conductance. A Frenkel defect, i.e., a superposition of an O interstitial and O substitutional defect, leads to a remarkably high conductance. From the analysis of the defect formation energies, Cu vacancies are found to be particularly stable, in agreement with earlier experimental and theoretical work.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016PhRvB..94w5448P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016PhRvB..94w5448P"><span id="translatedtitle">Spin-polarized <span class="hlt">electron</span> <span class="hlt">transport</span> through helicene molecular junctions</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Pan, Ting-Rui; Guo, Ai-Min; Sun, Qing-Feng</p> <p>2016-12-01</p> <p>Recently, the spin-selectivity effect of chiral molecules has been attracting extensive and growing interest among the scientific communities. Here, we propose a model Hamiltonian to study spin-dependent <span class="hlt">electron</span> <span class="hlt">transport</span> through helicene molecules which are connected by two semi-infinite graphene nanoribbons and try to elucidate a recent experiment of the spin-selectivity effect observed in the helicene molecules. The results indicate that the helicene molecules can present a significant spin-filtering effect in the case of extremely weak spin-orbit coupling, which is three orders of magnitude smaller than the hopping integral. The underlying physics is attributed to intrinsic chiral symmetry of the helicene molecules. When the chirality is switched from the right-handed species to the left-handed species, the spin polarization is reversed exactly. These results are consistent with a recent experiment [V. Kiran et al., Adv. Mater. 28, 1957 (2016), 10.1002/adma.201504725]. In addition, the spin-filtering effect of the helicene molecules is robust against molecular lengths, dephasing strengths, and space position disorder. This theoretical work may motivate further studies on chiral-induced spin selectivity in molecular systems.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/1009941','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/1009941"><span id="translatedtitle">Nonequilibrium <span class="hlt">electronic</span> <span class="hlt">transport</span> in a one-dimensional Mott insulator</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Heidrich-Meisner, F.; Gonzalez, Ivan; Al-Hassanieh, K. A.; Feiguin, A. E.; Rozenberg, M. J.; Dagotto, Elbio R</p> <p>2010-01-01</p> <p>We calculate the nonequilibrium <span class="hlt">electronic</span> <span class="hlt">transport</span> properties of a one-dimensional interacting chain at half filling, coupled to noninteracting leads. The interacting chain is initially in a Mott insulator state that is driven out of equilibrium by applying a strong bias voltage between the leads. For bias voltages above a certain threshold we observe the breakdown of the Mott insulator state and the establishment of a steady-state elec- tronic current through the system. Based on extensive time-dependent density-matrix renormalization-group simulations, we show that this steady-state current always has the same functional dependence on voltage, independent of the microscopic details of the model and we relate the value of the threshold to the Lieb-Wu gap. We frame our results in terms of the Landau-Zener dielectric breakdown picture. Finally, we also discuss the real-time evolution of the current, and characterize the current-carrying state resulting from the breakdown of the Mott insulator by computing the double occupancy, the spin structure factor, and the entanglement entropy.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015NatSR...5E9667O','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015NatSR...5E9667O"><span id="translatedtitle"><span class="hlt">Electronic</span> <span class="hlt">transport</span> in two-dimensional high dielectric constant nanosystems</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ortuño, M.; Somoza, A. M.; Vinokur, V. M.; Baturina, T. I.</p> <p>2015-04-01</p> <p>There has been remarkable recent progress in engineering high-dielectric constant two dimensional (2D) materials, which are being actively pursued for applications in nanoelectronics in capacitor and memory devices, energy storage, and high-frequency modulation in communication devices. Yet many of the unique properties of these systems are poorly understood and remain unexplored. Here we report a numerical study of hopping conductivity of the lateral network of capacitors, which models two-dimensional insulators, and demonstrate that 2D long-range Coulomb interactions lead to peculiar size effects. We find that the characteristic energy governing <span class="hlt">electronic</span> <span class="hlt">transport</span> scales logarithmically with either system size or electrostatic screening length depending on which one is shorter. Our results are relevant well beyond their immediate context, explaining, for example, recent experimental observations of logarithmic size dependence of electric conductivity of thin superconducting films in the critical vicinity of superconductor-insulator transition where a giant dielectric constant develops. Our findings mark a radical departure from the orthodox view of conductivity in 2D systems as a local characteristic of materials and establish its macroscopic global character as a generic property of high-dielectric constant 2D nanomaterials.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19990071231','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19990071231"><span id="translatedtitle">Inner Magnetospheric Superthermal <span class="hlt">Electron</span> <span class="hlt">Transport</span>: Photoelectron and Plasma Sheet <span class="hlt">Electron</span> Sources</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Khazanov, G. V.; Liemohn, M. W.; Kozyra, J. U.; Moore, T. E.</p> <p>1998-01-01</p> <p>Two time-dependent kinetic models of superthermal <span class="hlt">electron</span> <span class="hlt">transport</span> are combined to conduct global calculations of the nonthermal <span class="hlt">electron</span> distribution function throughout the inner magnetosphere. It is shown that the energy range of validity for this combined model extends down to the superthermal-thermal intersection at a few eV, allowing for the calculation of the en- tire distribution function and thus an accurate heating rate to the thermal plasma. Because of the linearity of the formulas, the source terms are separated to calculate the distributions from the various populations, namely photoelectrons (PEs) and plasma sheet <span class="hlt">electrons</span> (PSEs). These distributions are discussed in detail, examining the processes responsible for their formation in the various regions of the inner magnetosphere. It is shown that convection, corotation, and Coulomb collisions are the dominant processes in the formation of the PE distribution function and that PSEs are dominated by the interplay between the drift terms. Of note is that the PEs propagate around the nightside in a narrow channel at the edge of the plasmasphere as Coulomb collisions reduce the fluxes inside of this and convection compresses the flux tubes inward. These distributions are then recombined to show the development of the total superthermal <span class="hlt">electron</span> distribution function in the inner magnetosphere and their influence on the thermal plasma. PEs usually dominate the dayside heating, with integral energy fluxes to the ionosphere reaching 10(exp 10) eV/sq cm/s in the plasmasphere, while heating from the PSEs typically does not exceed 10(exp 8) eV/sq cm/s. On the nightside, the inner plasmasphere is usually unheated by superthermal <span class="hlt">electrons</span>. A feature of these combined spectra is that the distribution often has upward slopes with energy, particularly at the crossover from PE to PSE dominance, indicating that instabilities are possible.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19800024817','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19800024817"><span id="translatedtitle">Survey of the plasma <span class="hlt">electron</span> <span class="hlt">environment</span> of Jupiter: A view from Voyager</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Scudder, J. D.; Sittler, E. C., Jr.; Bridge, H. S.</p> <p>1980-01-01</p> <p>The plasma <span class="hlt">environment</span> within Jupiter's bow shock is considered in terms of the in situ, calibrated <span class="hlt">electron</span> plasma measurements made between 10 eV and 5.95 keV by the Voyager plasma science experiment (PLS). Measurements were analyzed and corrected for spacecraft potential variations; the data were reduced to nearly model independent macroscopic parameters of the local <span class="hlt">electron</span> density and temperature. It is tentatively concluded that the radial temperature profile within the plasma sheet is caused by the intermixing of two different <span class="hlt">electron</span> populations that probably have different temporal histories and spatial paths to their local observation. The cool plasma source of the plasma sheet and spikes is probably the Io plasma torus and arrives in the plasma sheet as a result of flux tube interchange motions or other generalized <span class="hlt">transport</span> which can be accomplished without diverting the plasma from the centrifugal equator. The hot suprathermal populations in the plasma sheet have most recently come from the sparse, hot mid-latitude "bath" of <span class="hlt">electrons</span> which were directly observed juxtaposed to the plasma sheet.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://files.eric.ed.gov/fulltext/ED124397.pdf','ERIC'); return false;" href="http://files.eric.ed.gov/fulltext/ED124397.pdf"><span id="translatedtitle">Impact of <span class="hlt">Transportation</span> on the <span class="hlt">Environment</span> and Quality of Life.</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Schuster, James J.</p> <p></p> <p>This paper discusses the changing role of civil engineers in developed nations. <span class="hlt">Transportation</span> facilities generally follow a four phase approach before construction: long range systems planning, corridor location study, design location study, and final preparation of plans. Traditional engineering education emphasized the latter two phases but now…</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/5021927','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/5021927"><span id="translatedtitle"><span class="hlt">Transportation</span> of radionuclides in urban <span class="hlt">environs</span>: draft environmental assessment</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Finley, N.C.; Aldrich, D.C.; Daniel, S.L.; Ericson, D.M.; Henning-Sachs, C.; Kaestner, P.C.; Ortiz, N.R.; Sheldon, D.D.; Taylor, J.M.</p> <p>1980-07-01</p> <p>This report assesses the environmental consequences of the <span class="hlt">transportation</span> of radioactive materials in densely populated urban areas, including estimates of the radiological, nonradiological, and social impacts arising from this process. The chapters of the report and the appendices which follow detail the methodology and results for each of four causative event categories: incident free <span class="hlt">transport</span>, vehicular accidents, human errors or deviations from accepted quality assurance practices, and sabotage or malevolent acts. The numerical results are expressed in terms of the expected radiological and economic impacts from each. Following these discussions, alternatives to the current <span class="hlt">transport</span> practice are considered. Then, the detailed analysis is extended from a limited area of New York city to other urban areas. The appendices contain the data bases and specific models used to evaluate these impacts, as well as discussions of chemical toxicity and the social impacts of radioactive material <span class="hlt">transport</span> in urban areas. The latter are evaluated for each causative event category in terms of psychological, sociological, political, legal, and organizational impacts. The report is followed by an extensive bibliography covering the many fields of study which were required in performing the analysis.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1986WRR....22..519K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1986WRR....22..519K"><span id="translatedtitle">Groundwater <span class="hlt">Transport</span> of Strontium 90 in a Glacial Outwash <span class="hlt">Environment</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kipp, Kenneth L., Jr.; Stollenwerk, Kenneth G.; Grove, David B.</p> <p>1986-04-01</p> <p>As part of the investigation of groundwater contamination at a uranium-scrap recovery plant at Wood River Junction, Rhode Island, laboratory experiments led to the development of a model for predicting the <span class="hlt">transport</span> of strontium 90 in glacial outwash sediments based on an approximate mechanism for ion exchange. The multicomponent system was simplified to two components by regarding all exchangeable cations other than strontium 90 as a single component. The binary ion-exchange parameter was a function of the variable, total ion concentration. A one-dimensional solute <span class="hlt">transport</span> model was formulated to evaluate the time necessary for natural groundwater flow to remove the strontium 90 contamination plume from the groundwater system to the Pawcatuck River. The finite difference <span class="hlt">transport</span> equations were solved sequentially for total ion concentrations, then strontium 90 concentrations. Clay-free quartz and feldspar sands at the study site have little potential for strontium 90 sorption, and high calcium, magnesium, and sodium concentrations compete for the few ion exchange sites. As the total ion concentration plume moves out of the system, ion exchange of strontium 90 increases, reducing the strontium 90 concentration in the groundwater. Cleanout times predicted using the binary ion exchange mechanism were about two thirds of those predicted using a constant distribution coefficient. It is suggested that this type of model can simulate solute <span class="hlt">transport</span> more realistically in many groundwater systems where the total ion concentration is not constant.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://eric.ed.gov/?q=Biochemistry&pg=7&id=EJ1068668','ERIC'); return false;" href="http://eric.ed.gov/?q=Biochemistry&pg=7&id=EJ1068668"><span id="translatedtitle">Using Adobe Flash Animations of <span class="hlt">Electron</span> <span class="hlt">Transport</span> Chain to Teach and Learn Biochemistry</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Teplá, Milada; Klímová, Helena</p> <p>2015-01-01</p> <p>Teaching the subject of the <span class="hlt">electron</span> <span class="hlt">transport</span> chain is one of the most challenging aspects of the chemistry curriculum at the high school level. This article presents an educational program called "<span class="hlt">Electron</span> <span class="hlt">Transport</span> Chain" which consists of 14 visual animations including a biochemistry quiz. The program was created in the Adobe Flash…</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li class="active"><span>17</span></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_17 --> <div id="page_18" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li class="active"><span>18</span></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="341"> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/21910905','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/21910905"><span id="translatedtitle">Tuning the <span class="hlt">electronic</span> <span class="hlt">transport</span> properties of grapheme through functionalisation with fluorine.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Withers, Freddie; Russo, Saverio; Dubois, Marc; Craciun, Monica F</p> <p>2011-09-12</p> <p>We demonstrate the possibility to tune the <span class="hlt">electronic</span> <span class="hlt">transport</span> properties of graphene mono-layers and multi-layers by functionalisation with fluorine. For mono-layer samples, with increasing the fluorine content, we observe a transition from <span class="hlt">electronic</span> <span class="hlt">transport</span> through Mott variable range hopping (VRH) in two dimensions to Efros-Shklovskii VRH. Multi-layer fluorinated graphene with high concentration of fluorine show two-dimensional Mott VRH <span class="hlt">transport</span>, whereas CF0.28 multi-layer flakes exhibit thermally activated <span class="hlt">transport</span> through near neighbour hopping. Our experimental findings demonstrate that the ability to control the degree of functionalisation of graphene is instrumental to engineer different <span class="hlt">electronic</span> properties in graphene materials.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/1069163','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/1069163"><span id="translatedtitle"><span class="hlt">Transportation</span> Energy Futures Series: Effects of the Built <span class="hlt">Environment</span> on <span class="hlt">Transportation</span>: Energy Use, Greenhouse Gas Emissions, and Other Factors</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Porter, C. D.; Brown, A.; Dunphy, R. T.; Vimmerstedt, L.</p> <p>2013-03-01</p> <p>Planning initiatives in many regions and communities aim to reduce <span class="hlt">transportation</span> energy use, decrease emissions, and achieve related environmental benefits by changing land use. This report reviews and summarizes findings from existing literature on the relationship between the built <span class="hlt">environment</span> and <span class="hlt">transportation</span> energy use and greenhouse gas emissions, identifying results trends as well as potential future actions. The indirect influence of federal <span class="hlt">transportation</span> and housing policies, as well as the direct impact of municipal regulation on land use are examined for their effect on <span class="hlt">transportation</span> patterns and energy use. Special attention is given to the 'four D' factors of density, diversity, design and accessibility. The report concludes that policy-driven changes to the built <span class="hlt">environment</span> could reduce <span class="hlt">transportation</span> energy and GHG emissions from less than 1% to as much as 10% by 2050, the equivalent of 16%-18% of present-day urban light-duty-vehicle travel. This is one of a series of reports produced as a result of the <span class="hlt">Transportation</span> Energy Futures (TEF) project, a Department of Energy-sponsored multi-agency project initiated to pinpoint underexplored strategies for abating GHGs and reducing petroleum dependence related to <span class="hlt">transportation</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/1219931','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/1219931"><span id="translatedtitle"><span class="hlt">Transportation</span> Energy Futures Series. Effects of the Built <span class="hlt">Environment</span> on <span class="hlt">Transportation</span>. Energy Use, Greenhouse Gas Emissions, and Other Factors</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Porter, C. D.; Brown, A.; Dunphy, R. T.; Vimmerstedt, L.</p> <p>2013-03-15</p> <p>Planning initiatives in many regions and communities aim to reduce <span class="hlt">transportation</span> energy use, decrease emissions, and achieve related environmental benefits by changing land use. This report reviews and summarizes findings from existing literature on the relationship between the built <span class="hlt">environment</span> and <span class="hlt">transportation</span> energy use and greenhouse gas emissions, identifying results trends as well as potential future actions. The indirect influence of federal <span class="hlt">transportation</span> and housing policies, as well as the direct impact of municipal regulation on land use are examined for their effect on <span class="hlt">transportation</span> patterns and energy use. Special attention is given to the 'four D' factors of density, diversity, design and accessibility. The report concludes that policy-driven changes to the built <span class="hlt">environment</span> could reduce <span class="hlt">transportation</span> energy and GHG emissions from less than 1% to as much as 10% by 2050, the equivalent of 16%-18% of present-day urban light-duty-vehicle travel. This is one of a series of reports produced as a result of the <span class="hlt">Transportation</span> Energy Futures (TEF) project, a Department of Energy-sponsored multi-agency project initiated to pinpoint underexplored strategies for abating GHGs and reducing petroleum dependence related to <span class="hlt">transportation</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.gpo.gov/fdsys/pkg/CFR-2010-title41-vol3/pdf/CFR-2010-title41-vol3-sec102-118-65.pdf','CFR'); return false;" href="https://www.gpo.gov/fdsys/pkg/CFR-2010-title41-vol3/pdf/CFR-2010-title41-vol3-sec102-118-65.pdf"><span id="translatedtitle">41 CFR 102-118.65 - Can my agency receive <span class="hlt">electronic</span> billing for payment of <span class="hlt">transportation</span> services?</span></a></p> <p><a target="_blank" href="http://www.gpo.gov/fdsys/browse/collectionCfr.action?selectedYearFrom=2010&page.go=Go">Code of Federal Regulations, 2010 CFR</a></p> <p></p> <p>2010-07-01</p> <p>... <span class="hlt">electronic</span> billing for payment of <span class="hlt">transportation</span> services? 102-118.65 Section 102-118.65 Public Contracts and... <span class="hlt">Transportation</span> Services § 102-118.65 Can my agency receive <span class="hlt">electronic</span> billing for payment of <span class="hlt">transportation</span>... to use <span class="hlt">electronic</span> billing for the procurement and billing of <span class="hlt">transportation</span> services....</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.gpo.gov/fdsys/pkg/CFR-2011-title41-vol3/pdf/CFR-2011-title41-vol3-sec102-118-65.pdf','CFR2011'); return false;" href="https://www.gpo.gov/fdsys/pkg/CFR-2011-title41-vol3/pdf/CFR-2011-title41-vol3-sec102-118-65.pdf"><span id="translatedtitle">41 CFR 102-118.65 - Can my agency receive <span class="hlt">electronic</span> billing for payment of <span class="hlt">transportation</span> services?</span></a></p> <p><a target="_blank" href="http://www.gpo.gov/fdsys/browse/collectionCfr.action?selectedYearFrom=2011&page.go=Go">Code of Federal Regulations, 2011 CFR</a></p> <p></p> <p>2011-01-01</p> <p>... <span class="hlt">electronic</span> billing for payment of <span class="hlt">transportation</span> services? 102-118.65 Section 102-118.65 Public Contracts and... <span class="hlt">Transportation</span> Services § 102-118.65 Can my agency receive <span class="hlt">electronic</span> billing for payment of <span class="hlt">transportation</span>... to use <span class="hlt">electronic</span> billing for the procurement and billing of <span class="hlt">transportation</span> services....</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.gpo.gov/fdsys/pkg/FR-2012-04-02/pdf/2012-7804.pdf','FEDREG'); return false;" href="https://www.gpo.gov/fdsys/pkg/FR-2012-04-02/pdf/2012-7804.pdf"><span id="translatedtitle">77 FR 19747 - Notice of <span class="hlt">Transportation</span> Services' Transition from Paper to <span class="hlt">Electronic</span> Fare Media</span></a></p> <p><a target="_blank" href="http://www.gpo.gov/fdsys/browse/collection.action?collectionCode=FR">Federal Register 2010, 2011, 2012, 2013, 2014</a></p> <p></p> <p>2012-04-02</p> <p>... Office of the Secretary of <span class="hlt">Transportation</span> Notice of <span class="hlt">Transportation</span> Services' Transition from Paper to... implementation of <span class="hlt">electronic</span> distribution, and a limited paper voucher process, allows for the most effective and... distributed the qualified <span class="hlt">transportation</span> fringe benefit to participating Federal employees via a paper...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AIPC.1786o0002I','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AIPC.1786o0002I"><span id="translatedtitle">State-to-state kinetics and <span class="hlt">transport</span> properties of <span class="hlt">electronically</span> excited N and O atoms</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Istomin, V. A.; Kustova, E. V.</p> <p>2016-11-01</p> <p>A theoretical model of <span class="hlt">transport</span> properties in <span class="hlt">electronically</span> excited atomic gases in the state-to-state approach is developed. Different models for the collision diameters of atoms in excited states are discussed, and it is shown that the Slater-like models can be applied for the state-resolved <span class="hlt">transport</span> coefficient calculations. The influence of collision diameters of N and O atoms with <span class="hlt">electronic</span> degrees of freedom on the <span class="hlt">transport</span> properties is evaluated. Different distributions on the <span class="hlt">electronic</span> energy are considered for the calculation of <span class="hlt">transport</span> coefficients. For the Boltzmann-like distributions at temperatures greater than 15000 K, an important effect of <span class="hlt">electronic</span> excitation on the thermal conductivity and viscosity coefficients is found; the coefficients decrease significantly when many <span class="hlt">electronic</span> states are taken into account. It is shown that under hypersonic reentry conditions the impact of collision diameters on the <span class="hlt">transport</span> properties is not really important since the populations of high levels behind the shock waves are low.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5095899','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5095899"><span id="translatedtitle">Insights into the post-transcriptional regulation of the mitochondrial <span class="hlt">electron</span> <span class="hlt">transport</span> chain</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Sirey, Tamara M.; Ponting, Chris P.</p> <p>2016-01-01</p> <p>The regulation of the mitochondrial <span class="hlt">electron</span> <span class="hlt">transport</span> chain is central to the control of cellular homeostasis. There are significant gaps in our understanding of how the expression of the mitochondrial and nuclear genome-encoded components of the <span class="hlt">electron</span> <span class="hlt">transport</span> chain are co-ordinated, and how the assembly of the protein complexes that constitute the <span class="hlt">electron</span> <span class="hlt">transport</span> chain are regulated. Furthermore, the role post-transcriptional gene regulation may play in modulating these processes needs to be clarified. This review summarizes the current knowledge regarding the post-transcriptional gene regulation of the <span class="hlt">electron</span> <span class="hlt">transport</span> chain and highlights how noncoding RNAs may contribute significantly both to complex <span class="hlt">electron</span> <span class="hlt">transport</span> chain regulatory networks and to mitochondrial dysfunction. PMID:27911731</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016Nanos...8.5847Y','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016Nanos...8.5847Y"><span id="translatedtitle">A composite nanostructured <span class="hlt">electron-transport</span> layer for stable hole-conductor free perovskite solar cells: design and characterization</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Yu, Zhenhua; Qi, Fei; Liu, Pei; You, Sujian; Kondamareddy, Kiran Kumar; Wang, Changlei; Cheng, Nian; Bai, Sihang; Liu, Wei; Guo, Shishang; Zhao, Xing-Zhong</p> <p>2016-03-01</p> <p>A novel composite nanostructured titanium dioxide (TiO2) based <span class="hlt">electron-transport</span> layer (ETL) is designed by combining size blended nanoparticles (SBNP) and nanoarrays (NA) for efficient perovskite solar cell (PSC) applications. The composite nanostructured (SBNP + NA) ETL is successfully employed in hole-conductor free PSCs, there by achieving a stable device with a maximum efficiency of 13.5%. The improvement in the performance is attributed to the better charge <span class="hlt">transport</span> and lower recombination in the SBNP + NA ETL. Despite the stable high efficiency, SBNP + NA ETL based PSCs are advantageous owing to their low cost, ease of all-solution fabrication process in an open <span class="hlt">environment</span> and good reproducibility.A novel composite nanostructured titanium dioxide (TiO2) based <span class="hlt">electron-transport</span> layer (ETL) is designed by combining size blended nanoparticles (SBNP) and nanoarrays (NA) for efficient perovskite solar cell (PSC) applications. The composite nanostructured (SBNP + NA) ETL is successfully employed in hole-conductor free PSCs, there by achieving a stable device with a maximum efficiency of 13.5%. The improvement in the performance is attributed to the better charge <span class="hlt">transport</span> and lower recombination in the SBNP + NA ETL. Despite the stable high efficiency, SBNP + NA ETL based PSCs are advantageous owing to their low cost, ease of all-solution fabrication process in an open <span class="hlt">environment</span> and good reproducibility. <span class="hlt">Electronic</span> supplementary information (ESI) available: Details of the experimental section and ESI figures. See DOI: 10.1039/c5nr09045h</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3572443','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3572443"><span id="translatedtitle">Hot <span class="hlt">electron</span> <span class="hlt">transport</span> in a strongly correlated transition-metal oxide</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Rana, Kumari Gaurav; Yajima, Takeaki; Parui, Subir; Kemper, Alexander F.; Devereaux, Thomas P.; Hikita, Yasuyuki; Hwang, Harold Y.; Banerjee, Tamalika</p> <p>2013-01-01</p> <p>Oxide heterointerfaces are ideal for investigating strong correlation effects to <span class="hlt">electron</span> <span class="hlt">transport</span>, relevant for oxide-<span class="hlt">electronics</span>. Using hot-<span class="hlt">electrons</span>, we probe <span class="hlt">electron</span> <span class="hlt">transport</span> perpendicular to the La0.7Sr0.3MnO3 (LSMO)- Nb-doped SrTiO3 (Nb:STO) interface and find the characteristic hot-<span class="hlt">electron</span> attenuation length in LSMO to be 1.48 ± 0.10 unit cells (u.c.) at −1.9 V, increasing to 2.02 ± 0.16 u.c. at −1.3 V at room temperature. Theoretical analysis of this energy dispersion reveals the dominance of <span class="hlt">electron-electron</span> and polaron scattering. Direct visualization of the local <span class="hlt">electron</span> <span class="hlt">transport</span> shows different transmission at the terraces and at the step-edges. PMID:23429420</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/1096262','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/1096262"><span id="translatedtitle">Modeling <span class="hlt">electron</span> <span class="hlt">transport</span> in the presence of electric and magnetic fields.</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Fan, Wesley C.; Drumm, Clifton Russell; Pautz, Shawn D.; Turner, C. David</p> <p>2013-09-01</p> <p>This report describes the theoretical background on modeling <span class="hlt">electron</span> <span class="hlt">transport</span> in the presence of electric and magnetic fields by incorporating the effects of the Lorentz force on <span class="hlt">electron</span> motion into the Boltzmann <span class="hlt">transport</span> equation. Electromagnetic fields alter the <span class="hlt">electron</span> energy and trajectory continuously, and these effects can be characterized mathematically by differential operators in terms of <span class="hlt">electron</span> energy and direction. Numerical solution techniques, based on the discrete-ordinates and finite-element methods, are developed and implemented in an existing radiation <span class="hlt">transport</span> code, SCEPTRE.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016APS..MAR.G1179S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016APS..MAR.G1179S"><span id="translatedtitle">The <span class="hlt">electronic</span> and <span class="hlt">transport</span> properties of monolayer transition metal dichalcogenides: a complex band structure analysis</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Szczesniak, Dominik</p> <p></p> <p>Recently, monolayer transition metal dichalcogenides have attracted much attention due to their potential use in both nano- and opto-<span class="hlt">electronics</span>. In such applications, the <span class="hlt">electronic</span> and <span class="hlt">transport</span> properties of group-VIB transition metal dichalcogenides (MX2 , where M=Mo, W; X=S, Se, Te) are particularly important. Herein, new insight into these properties is presented by studying the complex band structures (CBS's) of MX2 monolayers while accounting for spin-orbit coupling effects. By using the symmetry-based tight-binding model a nonlinear generalized eigenvalue problem for CBS's is obtained. An efficient method for solving such class of problems is presented and gives a complete set of physically relevant solutions. Next, these solutions are characterized and classified into propagating and evanescent states, where the latter states present not only monotonic but also oscillatory decay character. It is observed that some of the oscillatory evanescent states create characteristic complex loops at the direct band gaps, which describe the tunneling currents in the MX2 materials. The importance of CBS's and tunneling currents is demonstrated by the analysis of the quantum <span class="hlt">transport</span> across MX2 monolayers within phase field matching theory. Present work has been prepared within the Qatar Energy and <span class="hlt">Environment</span> Research Institute (QEERI) grand challenge ATHLOC project (Project No. QEERI- GC-3008).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011NIMPB.269..232B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011NIMPB.269..232B"><span id="translatedtitle">A deterministic <span class="hlt">electron</span>, photon, proton and heavy ion <span class="hlt">transport</span> suite for the study of the Jovian moon Europa</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Badavi, Francis F.; Blattnig, Steve R.; Atwell, William; Nealy, John E.; Norman, Ryan B.</p> <p>2011-02-01</p> <p>A Langley research center (LaRC) developed deterministic suite of radiation <span class="hlt">transport</span> codes describing the propagation of <span class="hlt">electron</span>, photon, proton and heavy ion in condensed media is used to simulate the exposure from the spectral distribution of the aforementioned particles in the Jovian radiation <span class="hlt">environment</span>. Based on the measurements by the Galileo probe (1995-2003) heavy ion counter (HIC), the choice of trapped heavy ions is limited to carbon, oxygen and sulfur (COS). The deterministic particle <span class="hlt">transport</span> suite consists of a coupled <span class="hlt">electron</span> photon algorithm (CEPTRN) and a coupled light heavy ion algorithm (HZETRN). The primary purpose for the development of the <span class="hlt">transport</span> suite is to provide a means to the spacecraft design community to rapidly perform numerous repetitive calculations essential for <span class="hlt">electron</span>, photon, proton and heavy ion exposure assessment in a complex space structure. In this paper, the reference radiation <span class="hlt">environment</span> of the Galilean satellite Europa is used as a representative boundary condition to show the capabilities of the <span class="hlt">transport</span> suite. While the <span class="hlt">transport</span> suite can directly access the output <span class="hlt">electron</span> and proton spectra of the Jovian <span class="hlt">environment</span> as generated by the jet propulsion laboratory (JPL) Galileo interim radiation <span class="hlt">electron</span> (GIRE) model of 2003; for the sake of relevance to the upcoming Europa Jupiter system mission (EJSM), the JPL provided Europa mission fluence spectrum, is used to produce the corresponding depth dose curve in silicon behind a default aluminum shield of 100 mils (˜0.7 g/cm2). The <span class="hlt">transport</span> suite can also accept a geometry describing ray traced thickness file from a computer aided design (CAD) package and calculate the total ionizing dose (TID) at a specific target point within the interior of the vehicle. In that regard, using a low fidelity CAD model of the Galileo probe generated by the authors, the <span class="hlt">transport</span> suite was verified versus Monte Carlo (MC) simulation for orbits JOI-J35 of the Galileo probe</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/946455','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/946455"><span id="translatedtitle"><span class="hlt">Electrons</span> in a positive-ion beam with solenoid or quadrupole magnetic <span class="hlt">transport</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Molvik, A.W.; Kireeff Covo, M.; Cohen, R.; Coleman, J.; Sharp, W.; Bieniosek, F.; Friedman, A.; Roy, P.K.; Seidl, P.; Lund, S.M.; Faltens, A.; Vay, J.L.; Prost, L.</p> <p>2007-06-04</p> <p>The High Current Experiment (HCX) is used to study beam <span class="hlt">transport</span> and accumulation of <span class="hlt">electrons</span> in quadrupole magnets and the Neutralized Drift-Compression Experiment (NDCX) to study beam <span class="hlt">transport</span> through and accumulation of <span class="hlt">electrons</span> in magnetic solenoids. We find that both clearing and suppressor electrodes perform as intended, enabling <span class="hlt">electron</span> cloud densities to be minimized. Then, the measured beam envelopes in both quadrupoles and solenoids agree with simulations, indicating that theoretical beam current <span class="hlt">transport</span> limits are reliable, in the absence of <span class="hlt">electrons</span>. At the other extreme, reversing electrode biases with the solenoid <span class="hlt">transport</span> effectively traps <span class="hlt">electrons</span>; or, in quadrupole magnets, grounding the suppressor electrode allows <span class="hlt">electron</span> emission from the end wall to flood the beam, in both cases producing significant degradation in the beam.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/919961','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/919961"><span id="translatedtitle"><span class="hlt">Electrons</span> in a Positive-Ion Beam with Solenoid or Quadrupole Magnet <span class="hlt">Transport</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Molvik, A W; Cohen, R H; Friedman, A; Covo, M K; Lund, S M; Sharp, W M; Seidl, P A; Bieniosek, F M; Coleman, J E; Faltens, A; Roy, P K; Vay, J L; Prost, L</p> <p>2007-06-01</p> <p>The High Current Experiment (HCX) is used to study beam <span class="hlt">transport</span> and accumulation of <span class="hlt">electrons</span> in quadrupole magnets and the Neutralized Drift-Compression Experiment (NDCX) to study beam <span class="hlt">transport</span> through and accumulation of <span class="hlt">electrons</span> in magnetic solenoids. We find that both clearing and suppressor electrodes perform as intended, enabling <span class="hlt">electron</span> cloud densities to be minimized. Then, the measured beam envelopes in both quadrupoles and solenoids agree with simulations, indicating that theoretical beam current <span class="hlt">transport</span> limits are reliable, in the absence of <span class="hlt">electrons</span>. At the other extreme, reversing electrode biases with the solenoid <span class="hlt">transport</span> effectively traps <span class="hlt">electrons</span>; or, in quadrupole magnets, grounding the suppressor electrode allows <span class="hlt">electron</span> emission from the end wall to flood the beam, in both cases producing significant degradation in the beam.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/23698325','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/23698325"><span id="translatedtitle">Stepping stones in the <span class="hlt">electron</span> <span class="hlt">transport</span> from cells to electrodes in Geobacter sulfurreducens biofilms.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Bonanni, Pablo Sebastián; Massazza, Diego; Busalmen, Juan Pablo</p> <p>2013-07-07</p> <p>Geobacter sulfurreducens bacteria grow on biofilms and have the particular ability of using polarized electrodes as the final <span class="hlt">electron</span> acceptor of their respiratory chain. In these biofilms, <span class="hlt">electrons</span> are <span class="hlt">transported</span> through distances of more than 50 μm before reaching the electrode. The way in which <span class="hlt">electrons</span> are <span class="hlt">transported</span> across the biofilm matrix through such large distances remains under intense discussion. None of the two mechanisms proposed for explaining the process, <span class="hlt">electron</span> hopping through outer membrane cytochromes and metallic like conduction through conductive PilA filaments, can account for all the experimental evidence collected so far. Aiming at providing new elements for understanding the basis for <span class="hlt">electron</span> <span class="hlt">transport</span>, in this perspective article we present a modelled structure of Geobacter pilus. Its analysis in combination with already existing experimental evidence gives support to the proposal of the "stepping stone" mechanism, in which the combined action of pili and cytochromes allows long range <span class="hlt">electron</span> <span class="hlt">transport</span> through the biofilm.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016APS..DPPT10020T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016APS..DPPT10020T"><span id="translatedtitle">Comparison of the nonlocal <span class="hlt">electron</span> <span class="hlt">transport</span> phenomenon between LHD and TFTR</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Tamura, Naoki; Fredrickson, Eric; Inagaki, Shigeru; Ida, Katsumi; Tsuchiya, Hayato; Tokuzawa, Tokihiko; Itoh, Kimitaka; Nagayama, Yoshio; Yamada, Hiroshi; Morisaki, Tomohiro; LHD Team</p> <p>2016-10-01</p> <p>In order to gain a predictive capability to achieve high-performance fusion plasmas, a better understanding of <span class="hlt">electron</span> heat <span class="hlt">transport</span> in magnetically confined plasmas is highly required. Although recent experiments and simulations in the fusion research have revealed important characteristics of <span class="hlt">electron</span> heat <span class="hlt">transport</span>, there still are a number of outstanding issues in <span class="hlt">electron</span> heat <span class="hlt">transport</span> such as nonlocality, which is defined as an instant interaction of <span class="hlt">transport</span> at between distant locations. The nonlocality in <span class="hlt">electron</span> heat <span class="hlt">transport</span> is believed to be particularly prominent in a so-called nonlocal <span class="hlt">transport</span> phenomenon, a sudden jump in core <span class="hlt">electron</span> temperature right after an edge cooling, which has been firstly discovered in tokamak and recently done in helical device, the Large Helical Device (LHD). Experimental results obtained in the LHD provided new insights on the nonlocal <span class="hlt">transport</span> phenomenon. In this contribution, we will discuss and compare the nonlocal <span class="hlt">transport</span> phenomena observed in LHD and TFTR with analysis techniques developed for the LHD, which will provide a clearer understanding on the nonlocality in <span class="hlt">electron</span> heat <span class="hlt">transport</span>. This work is supported by Japan/U.S. Cooperation in Fusion Research and Development.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/22304567','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/22304567"><span id="translatedtitle">Stability, <span class="hlt">electronic</span> structures and <span class="hlt">transport</span> properties of armchair (10, 10) BN/C nanotubes</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Xiao, H.P.; He, Chaoyu; Zhang, C.X.; Sun, L.Z.; Zhou, Pan; Zhong, Jianxin</p> <p>2013-04-15</p> <p>Using the first-principle calculations, the stability and <span class="hlt">electronic</span> properties of two novel types of four-segment armchair (10, 10) BN/C hybrid nanotubes ((BN){sub 5}C{sub 5}(BN){sub 5}C{sub 5}NT and (BN){sub 5}C{sub 5}(NB){sub 5}C{sub 5}NT) as well as two-segment armchair (10, 10) BN/C hybrid nanotubes ((BN{sub 20−n}C{sub n}NTs) are systematically investigated. When n increases from 1 to 4, the band gap of (BN){sub 20−n}C{sub n}NTs gradually decreases to a narrow one. When 4≤n≤17, the <span class="hlt">electronic</span> structure of carbon segment in (BN){sub 20−n}C{sub n}NTs behaves as zigzag graphene nanoribbons whose band gap is modulated by an inherent electric field of the BN segment. ZGNR-like segments in (BN){sub 5}C{sub 5}(BN){sub 5}C{sub 5}NT and (BN){sub 5}C{sub 5}(NB){sub 5}C{sub 5}NT behave as narrow gap semiconductor and metal, respectively, due to their different chemical <span class="hlt">environment</span>. Moreover, the (BN){sub 5}C{sub 5}(NB){sub 5}C{sub 5}NT can separate <span class="hlt">electron</span> and hole carriers, indicating its potential application in solar cell materials. Obvious <span class="hlt">transport</span> enhancement around the Fermi level is found in the four-segment nanotubes, especially a 6G{sub 0} transmission peak in the metallic (BN){sub 5}C{sub 5}(NB){sub 5}C{sub 5}NT. - Graphical abstract: Structural diagram of four-segment (BN){sub 5}C{sub 5}(NB){sub 5}C{sub 5}NT and its typical two-probe system. The band structures and <span class="hlt">transport</span> spectra of (BN){sub 5}C{sub 5}(NB){sub 5}C{sub 5}NT are shown in upper and lower panels. Highlights: ► <span class="hlt">Transport</span> properties of two types of four-segment BNC hybrid nanotubes are studied. ► <span class="hlt">Transport</span> enhancements are realized in the four-segment BNC hybrid nanotubes. ► <span class="hlt">Electron</span> and hole separation is found in four-segment BNC hybrid nanotubes.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017PhRvB..95k5416S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017PhRvB..95k5416S"><span id="translatedtitle">Landauer-Büttiker approach for hyperfine mediated <span class="hlt">electronic</span> <span class="hlt">transport</span> in the integer quantum Hall regime</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Singha, Aniket; Fauzi, M. H.; Hirayama, Y.; Muralidharan, Bhaskaran</p> <p>2017-03-01</p> <p>The interplay of spin-polarized <span class="hlt">electronic</span> edge states with the dynamics of the host nuclei in quantum Hall systems presents rich and nontrivial <span class="hlt">transport</span> physics. Here, we develop a Landauer-Büttiker approach to understand various experimental features observed in the integer quantum Hall setups featuring quantum point contacts. The approach developed here entails a phenomenological description of spin-resolved interedge scattering induced via hyperfine assisted <span class="hlt">electron</span>-nuclear spin flip-flop processes. A self-consistent simulation framework between the nuclear spin dynamics and edge state <span class="hlt">electronic</span> <span class="hlt">transport</span> is presented in order to gain crucial insights into the dynamic nuclear polarization effects on <span class="hlt">electronic</span> <span class="hlt">transport</span> and in turn the <span class="hlt">electron</span>-spin polarization effects on the nuclear spin dynamics. In particular, we show that the hysteresis noted experimentally in the conductance-voltage trace as well as in the resistively detected NMR line-shape results from a lack of quasiequilibrium between <span class="hlt">electronic</span> <span class="hlt">transport</span> and nuclear polarization evolution. In addition, we present circuit models to emulate such hyperfine mediated <span class="hlt">transport</span> effects to further facilitate a clear understanding of the <span class="hlt">electronic</span> <span class="hlt">transport</span> processes occurring around the quantum point contact. Finally, we extend our model to account for the effects of quadrupolar splitting of nuclear levels and also depict the <span class="hlt">electronic</span> <span class="hlt">transport</span> signatures that arise from single and multiphoton processes.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://cfpub.epa.gov/si/si_public_record_report.cfm?dirEntryId=318201&keyword=Scientific+AND+Work&actType=&TIMSType=+&TIMSSubTypeID=&DEID=&epaNumber=&ntisID=&archiveStatus=Both&ombCat=Any&dateBeginCreated=&dateEndCreated=&dateBeginPublishedPresented=&dateEndPublishedPresented=&dateBeginUpdated=&dateEndUpdated=&dateBeginCompleted=&dateEndCompleted=&personID=&role=Any&journalID=&publisherID=&sortBy=revisionDate&count=50&CFID=78751495&CFTOKEN=85972416','EPA-EIMS'); return false;" href="http://cfpub.epa.gov/si/si_public_record_report.cfm?dirEntryId=318201&keyword=Scientific+AND+Work&actType=&TIMSType=+&TIMSSubTypeID=&DEID=&epaNumber=&ntisID=&archiveStatus=Both&ombCat=Any&dateBeginCreated=&dateEndCreated=&dateBeginPublishedPresented=&dateEndPublishedPresented=&dateBeginUpdated=&dateEndUpdated=&dateBeginCompleted=&dateEndCompleted=&personID=&role=Any&journalID=&publisherID=&sortBy=revisionDate&count=50&CFID=78751495&CFTOKEN=85972416"><span id="translatedtitle">The association between green neighborhood <span class="hlt">environments</span> and active <span class="hlt">transportation</span></span></a></p> <p><a target="_blank" href="http://oaspub.epa.gov/eims/query.page">EPA Science Inventory</a></p> <p></p> <p></p> <p>Background: Urban nature is an important aspect of health-promoting <span class="hlt">environments</span>. In particular, street trees and green space can provide a low cost approach to improving public health by promoting physical activity, improving mental health, and facilitating social cohesion. Acti...</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li class="active"><span>18</span></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_18 --> <div id="page_19" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li class="active"><span>19</span></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="361"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20070020429','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20070020429"><span id="translatedtitle">Radiation-Hardened <span class="hlt">Electronics</span> for the Space <span class="hlt">Environment</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Keys, Andrew S.; Watson, Michael D.</p> <p>2007-01-01</p> <p>RHESE covers a broad range of technology areas and products. - Radiation Hardened <span class="hlt">Electronics</span> - High Performance Processing - Reconfigurable Computing - Radiation Environmental Effects Modeling - Low Temperature Radiation Hardened <span class="hlt">Electronics</span>. RHESE has aligned with currently defined customer needs. RHESE is leveraging/advancing SOA space <span class="hlt">electronics</span>, not duplicating. - Awareness of radiation-related activities through out government and industry allow advancement rather than duplication of capabilities.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/24671086','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/24671086"><span id="translatedtitle">Natural occurrence of microbial sulphur oxidation by long-range <span class="hlt">electron</span> <span class="hlt">transport</span> in the seafloor.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Malkin, Sairah Y; Rao, Alexandra M F; Seitaj, Dorina; Vasquez-Cardenas, Diana; Zetsche, Eva-Maria; Hidalgo-Martinez, Silvia; Boschker, Henricus T S; Meysman, Filip J R</p> <p>2014-09-01</p> <p>Recently, a novel mode of sulphur oxidation was described in marine sediments, in which sulphide oxidation in deeper anoxic layers was electrically coupled to oxygen reduction at the sediment surface. Subsequent experimental evidence identified that long filamentous bacteria belonging to the family Desulfobulbaceae likely mediated the <span class="hlt">electron</span> <span class="hlt">transport</span> across the centimetre-scale distances. Such long-range <span class="hlt">electron</span> transfer challenges some long-held views in microbial ecology and could have profound implications for sulphur cycling in marine sediments. But, so far, this process of electrogenic sulphur oxidation has been documented only in laboratory experiments and so its imprint on the seafloor remains unknown. Here we show that the geochemical signature of electrogenic sulphur oxidation occurs in a variety of coastal sediment <span class="hlt">environments</span>, including a salt marsh, a seasonally hypoxic basin, and a subtidal coastal mud plain. In all cases, electrogenic sulphur oxidation was detected together with an abundance of Desulfobulbaceae filaments. Complementary laboratory experiments in intertidal sands demonstrated that mechanical disturbance by bioturbating fauna destroys the electrogenic sulphur oxidation signal. A survey of published geochemical data and 16S rRNA gene sequences identified that electrogenic sulphide oxidation is likely present in a variety of marine sediments with high sulphide generation and restricted bioturbation, such as mangrove swamps, aquaculture areas, seasonally hypoxic basins, cold sulphide seeps and possibly hydrothermal vent <span class="hlt">environments</span>. This study shows for the first time that electrogenic sulphur oxidation occurs in a wide range of marine sediments and that bioturbation may exert a dominant control on its natural distribution.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010APS..MARZ33004M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010APS..MARZ33004M"><span id="translatedtitle"><span class="hlt">Environment</span>-assisted quantum walks in excitonic energy <span class="hlt">transport</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Mohseni, Masoud; Rebentrost, Patrick; Lloyd, Seth; Aspuru-Guzik, Alan</p> <p>2010-03-01</p> <p>Long-lived quantum coherence has recently been observed experimentally via ultrafast nonlinear spectroscopy in excitonic energy transfer within light-harvesting photosynthetic complexes, conjugated polymers, and marine alga even at room temperature. Here, we demonstrate that directed quantum walks lead to an enhancement of energy transfer efficiency in such systems. We introduce two complementary theoretical approaches, based on a Green's function method and energy transfer susceptibilities, to partition open quantum dynamics. We quantify the role of fundamental physical processes involved in energy <span class="hlt">transport</span>. In particular, we examine the contributions of classical hopping, coherent excitonic Hamiltonian, and phonon-induced decoherence effects for pure dephasing, Markovian, and non-Markovian limits.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/26382153','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/26382153"><span id="translatedtitle">Bacterial <span class="hlt">transport</span> of colloids in liquid crystalline <span class="hlt">environments</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Trivedi, Rishi R; Maeda, Rina; Abbott, Nicholas L; Spagnolie, Saverio E; Weibel, Douglas B</p> <p>2015-11-21</p> <p>We describe the controlled <span class="hlt">transport</span> and delivery of non-motile eukaryotic cells and polymer microparticles by swimming bacteria suspended in nematic liquid crystals. The bacteria push reversibly attached cargo in a stable, unidirectional path (or along a complex patterned director field) over exceptionally long distances. Numerical simulations and analytical predictions for swimming speeds provide a mechanistic insight into the hydrodynamics of the system. This study lays the foundation for using cargo-carrying bacteria in engineering applications and for understanding interspecies interactions in polymicrobial communities.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://files.eric.ed.gov/fulltext/ED423842.pdf','ERIC'); return false;" href="http://files.eric.ed.gov/fulltext/ED423842.pdf"><span id="translatedtitle">Creating <span class="hlt">Electronic</span> Learning <span class="hlt">Environments</span>: Games, Flow, and the User Interface.</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Jones, Marshall G.</p> <p></p> <p>A difficult task in creating rich, exploratory interactive learning <span class="hlt">environments</span> is building an <span class="hlt">environment</span> that is truly engaging. Engagement can be defined as the nexus of intrinsic knowledge and/or interest and external stimuli that promote the initial interest in, and continued use of a computer-based learning <span class="hlt">environment</span>. Complete and total…</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFM.H21A1327M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFM.H21A1327M"><span id="translatedtitle">Adaptive Mesh Refinement in Reactive <span class="hlt">Transport</span> Modeling of Subsurface <span class="hlt">Environments</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Molins, S.; Day, M.; Trebotich, D.; Graves, D. T.</p> <p>2015-12-01</p> <p>Adaptive mesh refinement (AMR) is a numerical technique for locally adjusting the resolution of computational grids. AMR makes it possible to superimpose levels of finer grids on the global computational grid in an adaptive manner allowing for more accurate calculations locally. AMR codes rely on the fundamental concept that the solution can be computed in different regions of the domain with different spatial resolutions. AMR codes have been applied to a wide range of problem including (but not limited to): fully compressible hydrodynamics, astrophysical flows, cosmological applications, combustion, blood flow, heat transfer in nuclear reactors, and land ice and atmospheric models for climate. In subsurface applications, in particular, reactive <span class="hlt">transport</span> modeling, AMR may be particularly useful in accurately capturing concentration gradients (hence, reaction rates) that develop in localized areas of the simulation domain. Accurate evaluation of reaction rates is critical in many subsurface applications. In this contribution, we will discuss recent applications that bring to bear AMR capabilities on reactive <span class="hlt">transport</span> problems from the pore scale to the flood plain scale.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/22267710','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/22267710"><span id="translatedtitle">Nonadiabatic <span class="hlt">electron</span> dynamics of single-<span class="hlt">electron</span> <span class="hlt">transport</span> in a perpendicular magnetic field</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>He, JianHong; Guo, HuaZhong; Gao, Jie</p> <p>2014-04-28</p> <p>We present results of our investigation into the nonadiabatic <span class="hlt">electron</span> dynamics of a moving quantum dot assisted by surface acoustic waves (SAWs) in a perpendicular magnetic field. The measurements show the evolution of a quantized acoustoelectric current in a modulated external field, which provides direct information of the energy spectrum and the occupation of the SAW-induced elliptical dynamical quantum dot. By comparing the magnetic field dependence of the spectrum with that of a somewhat symmetric circular dot, we find the appearance of nonadiabatic excitations at low magnetic fields resulting from the anisotropy of the dot. We also detect the transitions between different quantum states of the elliptical dot, achieved by exploiting the interference of two phase-tuned SAWs. Our results demonstrate that the quantum states in an asymmetric dot are fragile and extremely sensitive to their <span class="hlt">environment</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/27420809','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/27420809"><span id="translatedtitle">Competition of static magnetic and dynamic photon forces in <span class="hlt">electronic</span> <span class="hlt">transport</span> through a quantum dot.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Rauf Abdullah, Nzar; Tang, Chi-Shung; Manolescu, Andrei; Gudmundsson, Vidar</p> <p>2016-09-21</p> <p>We investigate theoretically the balance of the static magnetic and the dynamical photon forces in the <span class="hlt">electron</span> <span class="hlt">transport</span> through a quantum dot in a photon cavity with a single photon mode. The quantum dot system is connected to external leads and the total system is exposed to a static perpendicular magnetic field. We explore the <span class="hlt">transport</span> characteristics through the system by tuning the ratio, [Formula: see text], between the photon energy, [Formula: see text], and the cyclotron energy, [Formula: see text]. Enhancement in the <span class="hlt">electron</span> <span class="hlt">transport</span> with increasing <span class="hlt">electron</span>-photon coupling is observed when [Formula: see text]. In this case the photon field dominates and stretches the <span class="hlt">electron</span> charge distribution in the quantum dot, extending it towards the contact area for the leads. Suppression in the <span class="hlt">electron</span> <span class="hlt">transport</span> is found when [Formula: see text], as the external magnetic field causes circular confinement of the charge density around the dot.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/22218299','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/22218299"><span id="translatedtitle">The effect of <span class="hlt">electron</span> induced hydrogenation of graphene on its electrical <span class="hlt">transport</span> properties</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Woo, Sung Oh; Teizer, Winfried</p> <p>2013-07-22</p> <p>We report a deterioration of the electrical <span class="hlt">transport</span> properties of a graphene field effect transistor due to energetic <span class="hlt">electron</span> irradiation on a stack of Poly Methyl Methacrylate (PMMA) on graphene (PMMA/graphene bilayer). Prior to <span class="hlt">electron</span> irradiation, we observed that the PMMA layer on graphene does not deteriorate the carrier <span class="hlt">transport</span> of graphene but improves its electrical properties instead. As a result of the <span class="hlt">electron</span> irradiation on the PMMA/graphene bilayer, the Raman “D” band appears after removal of PMMA. We argue that the degradation of the <span class="hlt">transport</span> behavior originates from the binding of hydrogen generated during the PMMA backbone secession process.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19960021284&hterms=solar+energy+you&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D80%26Ntt%3Dsolar%2Benergy%2Byou','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19960021284&hterms=solar+energy+you&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D80%26Ntt%3Dsolar%2Benergy%2Byou"><span id="translatedtitle"><span class="hlt">Electron</span> energy <span class="hlt">transport</span> in the solar wind: Ulysses observations</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Scime, Earl; Gary, S. Peter; Phillips, J. L.; Corniileau-Wehrlin, N.; Solomon, J.</p> <p>1995-01-01</p> <p>The <span class="hlt">electron</span> heat flux in the solar wind has been measured by the Ulysses solar wind plasma experiment in the ecliptic from 1 to 5 AU and out of the ecliptic during the recently completed pass over the solar south pole and the ongoing pass over the solar north pole. Although the <span class="hlt">electron</span> heat flux contains only a fraction of the kinetic energy of the solar wind. the available energy is sufficient to account for the non-adiabatic expansion of the solar wind <span class="hlt">electrons</span>. The Ulysses measurements indicate that the <span class="hlt">electron</span> heat flux is actively dissipated in the solar wind. The exact mechanism or mechanisms is unknown. but a model based on the whistler heat flux instability predicts radial gradients for the <span class="hlt">electron</span> heat flux in good agreement with the data. We will present measurements of the correlation between wave activity measured by the unified radio and plasma experiment (URAP) and the <span class="hlt">electron</span> heat flux throughout the Ulysses mission. The goal is to determine if whistler waves are a good candidate for the observed <span class="hlt">electron</span> heat flux dissipation. The latitudinal gradients of the <span class="hlt">electron</span> heat flux. wave activity. and <span class="hlt">electron</span> pressure will be discussed in light of the changes in the magnetic field geometry from equator to poles.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/26436251','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/26436251"><span id="translatedtitle">Microbial <span class="hlt">Transport</span> and Fate in the Subsurface <span class="hlt">Environment</span>: Introduction to the Special Section.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Bradford, Scott A; Schijven, Jack; Harter, Thomas</p> <p>2015-09-01</p> <p>Microorganisms constitute an almost exclusive form of life in the earth's subsurface <span class="hlt">environment</span> (not including caves), particularly at depths exceeding the soil horizon. While of broad interest to ecology and geology, scientific interest in the fate and <span class="hlt">transport</span> of microorganisms, particularly those introduced through the anthropogenic <span class="hlt">environment</span>, has focused on understanding the subsurface <span class="hlt">environment</span> as a pathway for human pathogens and on optimizing the use of microbial organisms for remediation of potable groundwater. This special section, inspired by the 2014 Ninth International Symposium for Subsurface Microbiology, brings together recent efforts to better understand the spatiotemporal occurrence of anthropogenic microbial groundwater contamination and the fate and <span class="hlt">transport</span> of microbes in the subsurface <span class="hlt">environment</span>: in soils, deep unsaturated zones, and within aquifer systems. Work includes field reconnaissance, controlled laboratory studies to improve our understanding of specific fate and <span class="hlt">transport</span> processes, and the development and application of improved mechanistic understanding of microbial fate and <span class="hlt">transport</span> processes in the subsurface <span class="hlt">environment</span>. The findings confirm and also challenge the limitations of our current understanding of highly complex microbial fate and <span class="hlt">transport</span> processes across spatiotemporal scales in the subsurface <span class="hlt">environment</span>; they also add to the increasing knowledge base to improve our ability to protect drinking water resources and perform in situ environmental remediation.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016CoPhC.203..268R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016CoPhC.203..268R"><span id="translatedtitle">METHES: A Monte Carlo collision code for the simulation of <span class="hlt">electron</span> <span class="hlt">transport</span> in low temperature plasmas</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Rabie, M.; Franck, C. M.</p> <p>2016-06-01</p> <p>We present a freely available MATLAB code for the simulation of <span class="hlt">electron</span> <span class="hlt">transport</span> in arbitrary gas mixtures in the presence of uniform electric fields. For steady-state <span class="hlt">electron</span> <span class="hlt">transport</span>, the program provides the <span class="hlt">transport</span> coefficients, reaction rates and the <span class="hlt">electron</span> energy distribution function. The program uses established Monte Carlo techniques and is compatible with the <span class="hlt">electron</span> scattering cross section files from the open-access Plasma Data Exchange Project LXCat. The code is written in object-oriented design, allowing the tracing and visualization of the spatiotemporal evolution of <span class="hlt">electron</span> swarms and the temporal development of the mean energy and the <span class="hlt">electron</span> number due to attachment and/or ionization processes. We benchmark our code with well-known model gases as well as the real gases argon, N2, O2, CF4, SF6 and mixtures of N2 and O2.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014AGUFMSM44A..03B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014AGUFMSM44A..03B"><span id="translatedtitle">Suprathermal <span class="hlt">Electrons</span> in the Plasma <span class="hlt">Environments</span> of Mars and Venus</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Brain, D. A.</p> <p>2014-12-01</p> <p>Suprathermal <span class="hlt">electrons</span> have been measured in situ at every planet in the solar system, as well as at many smaller solar system bodies. They are hallmarks of heating, acceleration, or non-equilibrium processes occurring in any plasma, and planets are no exception. After introducing the many planetary measurements that have been made over time, this presentation will focus on a subset of <span class="hlt">electron</span> measurements from Mars and Venus made over the last decade. At Mars, suprathermal <span class="hlt">electrons</span> are used as diagnostics of auroral acceleration in small-scale crustal fields, and the magnetic topology of the crustal fields. At Venus, <span class="hlt">electron</span> energy distributions are used to map the ionosphere, revealing previously unknown asymmetries. The presentation will close with a brief discussion of prospects for future and ongoing planetary <span class="hlt">electron</span> measurements.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/1020498','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/1020498"><span id="translatedtitle">Combustion chemistry and an evolving <span class="hlt">transportation</span> fuel <span class="hlt">environment</span>.</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Taatjes, Craig A.</p> <p>2010-05-01</p> <p>The world currently faces tremendous energy challenges stemming from the need to curb potentially catastrophic anthropogenic climate change. In addition, many nations, including the United States, recognize increasing political and economic risks associated with dependence on uncertain and limited energy sources. For these and other reasons the chemical composition of <span class="hlt">transportation</span> fuels is changing, both through introduction of nontraditional fossil sources, such as oil sands-derived fuels in the US stream, and through broader exploration of biofuels. At the same time the need for clean and efficient combustion is leading engine research towards advanced low-temperature combustion strategies that are increasingly sensitive to this changing fuel chemistry, particularly in the areas of pollutant formation and autoignition. I will highlight the new demands that advanced engine technologies and evolving fuel composition place on investigations of fundamental reaction chemistry. I will focus on recent progress in measuring product formation in elementary reactions by tunable synchrotron photoionization, on the elucidation of pressure-dependent effects in the reactions of alkyl and substituted alkyl radicals with O{sub 2}, and on new combined efforts in fundamental combustion chemistry and engine performance studies of novel potential biofuels.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1996AIPC..355..487C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1996AIPC..355..487C"><span id="translatedtitle"><span class="hlt">Electron</span> ripple injection concept for tokamak <span class="hlt">transport</span> control</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Choe, W.; Ono, M.; Chang, C. S.</p> <p>1996-02-01</p> <p>A non-intrusive method for inducing a radial electric field (Er) based on <span class="hlt">electron</span> ripple injection (ERI) is under development by the Princeton CDX-U group. Since Er is known to play an important role in the L-H and H-VH mode transition, it is therefore important to develop a non-intrusive tool to control the Er profile in tokamak plasmas. The present technique utilizes externally-applied local magnetic ripple fields to trap <span class="hlt">electrons</span> at the edge, allowing them to penetrate towards the plasma center via ∇B and curvature drifts, causing the flux surfaces to charge up negatively. <span class="hlt">Electron</span> cyclotron resonance heating (ECRH) is utilized to increase the trapped population and the <span class="hlt">electron</span> drift velocity by raising the perpendicular energy of trapped <span class="hlt">electrons</span>. The temperature anisotropy of resonant <span class="hlt">electrons</span> in a tokamak plasma is calculated in order to investigate effects of ECRH on <span class="hlt">electrons</span>. Simulations using a guiding-center orbit model have been performed to understand the behavior of suprathermal <span class="hlt">electrons</span> in the presence of ripple fields. Examples for CDX-U and ITER are given.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010cosp...38..714A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010cosp...38..714A"><span id="translatedtitle">Complex role of secondary <span class="hlt">electron</span> emissions in dust grain charging in space <span class="hlt">environments</span>: measurements on Apollo 11 & 17 dust grains</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Abbas, Mian; Tankosic, Dragana; Spann, James; Leclair, Andre C.</p> <p></p> <p>Dust grains in various astrophysical <span class="hlt">environments</span> are generally charged electrostatically by photoelectric emissions with radiation from nearby sources, by <span class="hlt">electron</span>/ion collisions, and sec-ondary <span class="hlt">electron</span> emissions. Knowledge of the dust grain charges and equilibrium potentials is important for understanding of a variety of physical and dynamical processes in the interstel-lar medium (ISM), and heliospheric, interplanetary, planetary, and lunar <span class="hlt">environments</span>. The high vacuum <span class="hlt">environment</span> on the lunar surface leads to some unusual physical and dynam-ical phenomena involving dust grains with high adhesive characteristics, and levitation and <span class="hlt">transportation</span> over long distances. It has been well recognized that the charging properties of individual micron/submicron size dust grains are expected to be substantially different from the corresponding values for bulk materials and theoretical models. In this paper we present experimental results on charging of individual dust grains selected from Apollo 11 and Apollo 17 dust samples by exposing them to mono-energetic <span class="hlt">electron</span> beams in the 10-400 eV energy range. The charging rates of positively and negatively charged particles of 0.2 to 13 µm diam-eters are discussed in terms of the secondary <span class="hlt">electron</span> emission (SEE) process, which is found to be a complex charging process at <span class="hlt">electron</span> energies as low as 10-25 eV, with strong parti-cle size dependence. The measurements indicate substantial differences between dust charging properties of individual small size dust grains and of bulk materials.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/20698372','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/20698372"><span id="translatedtitle">Effect of <span class="hlt">electron</span> collisions on <span class="hlt">transport</span> coefficients induced by the inverse bremsstrahlung absorption in plasmas</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Bendib, A.; Tahraoui, A.; Bendib, K.; Mohammed El Hadj, K.; Hueller, S.</p> <p>2005-03-01</p> <p>The <span class="hlt">transport</span> coefficients of fully ionized plasmas under the influence of a high-frequency electric field are derived solving numerically the <span class="hlt">electron</span> Fokker-Planck equation using a perturbation method, parametrized as a function of the <span class="hlt">electron</span> mean-free-path {lambda}{sub ei} compared to the spatial scales L. The isotropic and anisotropic contributions of the inverse bremsstrahlung heating are considered. <span class="hlt">Electron-electron</span> collision terms are kept in the analysis, which allows us to consider with sufficient accuracy to describe plasmas with arbitrary atomic number Z. Practical numerical fits of the <span class="hlt">transport</span> coefficients are proposed as functions of Z and the collisionality parameter {lambda}{sub ei}/L.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.gpo.gov/fdsys/pkg/CFR-2010-title41-vol3/pdf/CFR-2010-title41-vol3-sec102-118-80.pdf','CFR'); return false;" href="https://www.gpo.gov/fdsys/pkg/CFR-2010-title41-vol3/pdf/CFR-2010-title41-vol3-sec102-118-80.pdf"><span id="translatedtitle">41 CFR 102-118.80 - Who is responsible for keeping my agency's <span class="hlt">electronic</span> commerce <span class="hlt">transportation</span> billing records?</span></a></p> <p><a target="_blank" href="http://www.gpo.gov/fdsys/browse/collectionCfr.action?selectedYearFrom=2010&page.go=Go">Code of Federal Regulations, 2010 CFR</a></p> <p></p> <p>2010-07-01</p> <p>... keeping my agency's <span class="hlt">electronic</span> commerce <span class="hlt">transportation</span> billing records? 102-118.80 Section 102-118.80... <span class="hlt">Transportation</span> and <span class="hlt">Transportation</span> Services § 102-118.80 Who is responsible for keeping my agency's <span class="hlt">electronic</span> commerce <span class="hlt">transportation</span> billing records? Your agency's internal financial regulations will...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.gpo.gov/fdsys/pkg/CFR-2012-title41-vol3/pdf/CFR-2012-title41-vol3-sec102-118-80.pdf','CFR2012'); return false;" href="https://www.gpo.gov/fdsys/pkg/CFR-2012-title41-vol3/pdf/CFR-2012-title41-vol3-sec102-118-80.pdf"><span id="translatedtitle">41 CFR 102-118.80 - Who is responsible for keeping my agency's <span class="hlt">electronic</span> commerce <span class="hlt">transportation</span> billing records?</span></a></p> <p><a target="_blank" href="http://www.gpo.gov/fdsys/browse/collectionCfr.action?selectedYearFrom=2012&page.go=Go">Code of Federal Regulations, 2012 CFR</a></p> <p></p> <p>2012-01-01</p> <p>... keeping my agency's <span class="hlt">electronic</span> commerce <span class="hlt">transportation</span> billing records? 102-118.80 Section 102-118.80... <span class="hlt">Transportation</span> and <span class="hlt">Transportation</span> Services § 102-118.80 Who is responsible for keeping my agency's <span class="hlt">electronic</span> commerce <span class="hlt">transportation</span> billing records? Your agency's internal financial regulations will...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.gpo.gov/fdsys/pkg/CFR-2013-title41-vol3/pdf/CFR-2013-title41-vol3-sec102-118-80.pdf','CFR2013'); return false;" href="https://www.gpo.gov/fdsys/pkg/CFR-2013-title41-vol3/pdf/CFR-2013-title41-vol3-sec102-118-80.pdf"><span id="translatedtitle">41 CFR 102-118.80 - Who is responsible for keeping my agency's <span class="hlt">electronic</span> commerce <span class="hlt">transportation</span> billing records?</span></a></p> <p><a target="_blank" href="http://www.gpo.gov/fdsys/browse/collectionCfr.action?selectedYearFrom=2013&page.go=Go">Code of Federal Regulations, 2013 CFR</a></p> <p></p> <p>2013-07-01</p> <p>... keeping my agency's <span class="hlt">electronic</span> commerce <span class="hlt">transportation</span> billing records? 102-118.80 Section 102-118.80... <span class="hlt">Transportation</span> and <span class="hlt">Transportation</span> Services § 102-118.80 Who is responsible for keeping my agency's <span class="hlt">electronic</span> commerce <span class="hlt">transportation</span> billing records? Your agency's internal financial regulations will...</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li class="active"><span>19</span></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_19 --> <div id="page_20" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li class="active"><span>20</span></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="381"> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.gpo.gov/fdsys/pkg/CFR-2014-title41-vol3/pdf/CFR-2014-title41-vol3-sec102-118-80.pdf','CFR2014'); return false;" href="https://www.gpo.gov/fdsys/pkg/CFR-2014-title41-vol3/pdf/CFR-2014-title41-vol3-sec102-118-80.pdf"><span id="translatedtitle">41 CFR 102-118.80 - Who is responsible for keeping my agency's <span class="hlt">electronic</span> commerce <span class="hlt">transportation</span> billing records?</span></a></p> <p><a target="_blank" href="http://www.gpo.gov/fdsys/browse/collectionCfr.action?selectedYearFrom=2014&page.go=Go">Code of Federal Regulations, 2014 CFR</a></p> <p></p> <p>2014-01-01</p> <p>... keeping my agency's <span class="hlt">electronic</span> commerce <span class="hlt">transportation</span> billing records? 102-118.80 Section 102-118.80... <span class="hlt">Transportation</span> and <span class="hlt">Transportation</span> Services § 102-118.80 Who is responsible for keeping my agency's <span class="hlt">electronic</span> commerce <span class="hlt">transportation</span> billing records? Your agency's internal financial regulations will...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014PhDT.......352S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014PhDT.......352S"><span id="translatedtitle"><span class="hlt">Electronic</span> structure and quantum <span class="hlt">transport</span> properties of metallic and semiconducting nanowires</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Simbeck, Adam J.</p> <p></p> <p>The future of the semiconductor industry hinges upon new developments to combat the scaling issues that currently afflict two main chip components: transistors and interconnects. For transistors this means investigating suitable materials to replace silicon for both the insulating gate and the semiconducting channel in order to maintain device performance with decreasing size. For interconnects this equates to overcoming the challenges associated with copper when the wire dimensions approach the confinement limit, as well as continuing to develop low-k dielectric materials that can assure minimal cross-talk between lines. In addition, such challenges make it increasingly clear that device design must move from a top-down to a bottom-up approach in which the desired <span class="hlt">electronic</span> characteristics are tailored from first-principles. It is with such fundamental hurdles in mind that ab initio calculations on the <span class="hlt">electronic</span> and quantum <span class="hlt">transport</span> properties of nanoscale metallic and semiconducting wires have been performed. More specifically, this study seeks to elaborate on the role played by confinement, contacts, dielectric <span class="hlt">environment</span>, edge decoration, and defects in altering the <span class="hlt">electronic</span> and <span class="hlt">transport</span> characteristics of such systems. As experiments continue to achieve better control over the synthesis and design of nanowires, these results are expected to become increasingly more important for not only the interpretation of <span class="hlt">electronic</span> and <span class="hlt">transport</span> trends, but also in engineering the <span class="hlt">electronic</span> structure of nanowires for the needs of the devices of the future. For the metallic atomic wires, the quantum <span class="hlt">transport</span> properties are first investigated by considering finite, single-atom chains of aluminum, copper, gold, and silver sandwiched between gold contacts. Non-equilibrium Green's function based <span class="hlt">transport</span> calculations reveal that even in the presence of the contact the conductivity of atomic-scale aluminum is greater than that of the other metals considered. This is</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2004CP....299...89V','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2004CP....299...89V"><span id="translatedtitle">Correlating substituent parameter values to <span class="hlt">electron</span> <span class="hlt">transport</span> properties of molecules</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Vedova-Brook, Natalie; Matsunaga, Nikita; Sohlberg, Karl</p> <p>2004-03-01</p> <p>There are a vast number of organic compounds that could be considered for use in molecular <span class="hlt">electronics</span>. Because of this, the need for efficient and economical screening tools has emerged. We demonstrate that the substituent parameter values ( σ), commonly found in advanced organic chemistry textbooks, correlate strongly with features of the charge migration process, establishing them as useful indicators of <span class="hlt">electronic</span> properties. Specifically, we report that ab initio derived <span class="hlt">electronic</span> charge transfer values for 16 different substituted aromatic molecules for molecular junctions correlate to the σ values with a correlation coefficient squared ( R2) of 0.863.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.dtic.mil/docs/citations/ADA638603','DTIC-ST'); return false;" href="http://www.dtic.mil/docs/citations/ADA638603"><span id="translatedtitle">Temperature Dependent <span class="hlt">Electron</span> <span class="hlt">Transport</span> Studies for Diffuse Discharge Switching Applications</span></a></p> <p><a target="_blank" href="https://publicaccess.dtic.mil/psm/api/service/search/search">DTIC Science & Technology</a></p> <p></p> <p>1985-06-01</p> <p>of <e>, k (<e >), for C2F6 and C3F8 at gas temperature up to 7!fu K. These results may be used to under stand the influence of elevated gas...of k (<&>) have also been performed in c3F8 as a functionaof gas temperature up to 750 R in Ar buffer gas (over the mean <span class="hlt">electron</span> energy range 0.76...dependent <span class="hlt">electron</span> attachment pro- cesses are negligible indicating that <span class="hlt">electron</span> attachment to C3F8 at t hese t emperatures i s predomi- nantly dissociati</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/22490743','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/22490743"><span id="translatedtitle">Color stable white phosphorescent organic light emitting diodes with red emissive <span class="hlt">electron</span> <span class="hlt">transport</span> layer</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Wook Kim, Jin; Yoo, Seung Il; Sung Kang, Jin; Eun Lee, Song; Kwan Kim, Young; Hwa Yu, Hyeong; Turak, Ayse; Young Kim, Woo</p> <p>2015-06-28</p> <p>We analyzed the performance of multi-emissive white phosphorescent organic light-emitting diodes (PHOLEDs) in relation to various red emitting sites of hole and <span class="hlt">electron</span> <span class="hlt">transport</span> layers (HTL and ETL). The shift of the recombination zone producing stable white emission in PHOLEDs was utilized as luminance was increased with red emission in its <span class="hlt">electron</span> <span class="hlt">transport</span> layer. Multi-emissive white PHOLEDs including the red light emitting <span class="hlt">electron</span> <span class="hlt">transport</span> layer yielded maximum external quantum efficiency of 17.4% with CIE color coordinates (−0.030, +0.001) shifting only from 1000 to 10 000 cd/m{sup 2}. Additionally, we observed a reduction of energy loss in the white PHOLED via Ir(piq){sub 3} as phosphorescent red dopant in <span class="hlt">electron</span> <span class="hlt">transport</span> layer.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015JAP...117x5503W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015JAP...117x5503W"><span id="translatedtitle">Color stable white phosphorescent organic light emitting diodes with red emissive <span class="hlt">electron</span> <span class="hlt">transport</span> layer</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Wook Kim, Jin; Yoo, Seung Il; Sung Kang, Jin; Eun Lee, Song; Kwan Kim, Young; Hwa Yu, Hyeong; Turak, Ayse; Young Kim, Woo</p> <p>2015-06-01</p> <p>We analyzed the performance of multi-emissive white phosphorescent organic light-emitting diodes (PHOLEDs) in relation to various red emitting sites of hole and <span class="hlt">electron</span> <span class="hlt">transport</span> layers (HTL and ETL). The shift of the recombination zone producing stable white emission in PHOLEDs was utilized as luminance was increased with red emission in its <span class="hlt">electron</span> <span class="hlt">transport</span> layer. Multi-emissive white PHOLEDs including the red light emitting <span class="hlt">electron</span> <span class="hlt">transport</span> layer yielded maximum external quantum efficiency of 17.4% with CIE color coordinates (-0.030, +0.001) shifting only from 1000 to 10 000 cd/m2. Additionally, we observed a reduction of energy loss in the white PHOLED via Ir(piq)3 as phosphorescent red dopant in <span class="hlt">electron</span> <span class="hlt">transport</span> layer.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/22495003','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/22495003"><span id="translatedtitle">Decoupled <span class="hlt">electron</span> and phonon <span class="hlt">transports</span> in hexagonal boron nitride-silicene bilayer heterostructure</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Cai, Yongqing; Pei, Qing-Xiang E-mail: zhangg@ihpc.a-star.edu.sg; Zhang, Gang E-mail: zhangg@ihpc.a-star.edu.sg; Zhang, Yong-Wei</p> <p>2016-02-14</p> <p>Calculations based on the density functional theory and empirical molecular dynamics are performed to investigate interlayer interaction, <span class="hlt">electronic</span> structure and thermal <span class="hlt">transport</span> of a bilayer heterostructure consisting of silicene and hexagonal boron nitride (h-BN). In this heterostructure, the two layers are found to interact weakly via a non-covalent binding. As a result, the Dirac cone of silicene is preserved with the Dirac cone point being located exactly at the Fermi level, and only a small amount of <span class="hlt">electrons</span> are transferred from h-BN to silicene, suggesting that silicene dominates the <span class="hlt">electronic</span> <span class="hlt">transport</span>. Molecular dynamics calculation results demonstrate that the heat current along h-BN is six times of that along silicene, suggesting that h-BN dominates the thermal <span class="hlt">transport</span>. This decoupled role of h-BN and silicene in thermal and <span class="hlt">electronic</span> <span class="hlt">transport</span> suggests that the BN-silicene bilayer heterostructure is promising for thermoelectric applications.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2003AnP...515..471S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2003AnP...515..471S"><span id="translatedtitle">Quasiclassical theory of charge <span class="hlt">transport</span> in disordered interacting <span class="hlt">electron</span> systems</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Schwab, P.; Raimondi, R.</p> <p>2003-10-01</p> <p>We consider the corrections to the Boltzmann theory of electrical <span class="hlt">transport</span> arising from the Coulomb interaction in disordered conductors. In this article the theory is formulated in terms of quasiclassical Green's functions. We demonstrate that the formalism is equivalent to the conventional diagrammatic technique by deriving the well-known Altshuler-Aronov corrections to the conductivity. Compared to the conventional approach, the quasiclassical theory has the advantage of being closer to the Boltzmann theory, and also allows description of interaction effects in the <span class="hlt">transport</span> across interfaces, as well as non-equilibrium phenomena in the same theoretical framework. As an example, by applying the Zaitsev boundary conditions which were originally developed for superconductors, we obtain the P(E)-theory of the Coulomb blockade in tunnel junctions. Furthermore we summarize recent results obtained for the non-equilibrium <span class="hlt">transport</span> in thin films, wires and fully coherent conductors.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/24581058','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/24581058"><span id="translatedtitle">Relationships between the perceived neighborhood social <span class="hlt">environment</span> and walking for <span class="hlt">transportation</span> among older adults.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Van Cauwenberg, Jelle; De Donder, Liesbeth; Clarys, Peter; De Bourdeaudhuij, Ilse; Buffel, Tine; De Witte, Nico; Dury, Sarah; Verté, Dominique; Deforche, Benedicte</p> <p>2014-03-01</p> <p>Ecological models state that physical activity (PA) behaviors can be explained by the interplay between individuals and their surrounding physical and social <span class="hlt">environment</span>. However, the majority of research on PA-<span class="hlt">environment</span> relationships has focused upon the physical <span class="hlt">environment</span>. The purpose of the current study was to investigate the relationship between the perceived social <span class="hlt">environment</span> and older adults' walking for <span class="hlt">transportation</span>, while adjusting for individual and perceived physical environmental factors. Questionnaires were used to collect data on walking for <span class="hlt">transportation</span>, individual, perceived physical and social environmental factors in 50,986 Flemish older adults (≥65 years) in the period of 2004-2010. Multilevel logistic regression analyses were applied to examine the relationships between perceived social environmental factors and the odds of daily walking for <span class="hlt">transportation</span>. The final models showed significant positive relationships for frequency of contacts with neighbors, neighbors' social support, too many immigrants residing in the neighborhood, neighborhood involvement, participation, and volunteering. These results emphasize the need for including social environmental factors in future studies examining correlates of older adults' physical activity. Current findings suggest that projects stimulating interpersonal relationships, place attachment, and formal community engagement might promote walking for <span class="hlt">transportation</span> among older adults. Future research should try to further disentangle the complex (inter)relationships and causal mechanisms between older individuals, their <span class="hlt">environments</span>, and their walking for <span class="hlt">transportation</span> behavior.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/1206544','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/1206544"><span id="translatedtitle">Ultrafast <span class="hlt">electron</span> <span class="hlt">transport</span> across nano gaps in nanowire circuits</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Potma, Eric O.</p> <p>2015-07-31</p> <p>In this Program we aim for a closer look at <span class="hlt">electron</span> transfer through single molecules. To achieve this, we use ultrafast laser pulses to time stamp an <span class="hlt">electron</span> tunneling event in a molecule that is connected between two metallic electrodes, while reading out the <span class="hlt">electron</span> current. A key aspect of this project is the use of metallic substrates with plasmonic activity to efficiently manipulate the tunneling probability. The first Phase of this program is concerned with developing highly sensitive tools for the ultrafast optical manipulation of tethered molecules through the evanescent surface field of plasmonic substrates. The second Phase of the program aims to use these tools for exercising control over the <span class="hlt">electron</span> tunneling probability.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/828197','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/828197"><span id="translatedtitle"><span class="hlt">Electron</span> Cross-field <span class="hlt">Transport</span> in a Low Power Cylindrical Hall Thruster</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>A. Smirnov; Y. Raitses; N.J. Fisch</p> <p>2004-06-24</p> <p>Conventional annular Hall thrusters become inefficient when scaled to low power. Cylindrical Hall thrusters, which have lower surface-to-volume ratio, are therefore more promising for scaling down. They presently exhibit performance comparable with conventional annular Hall thrusters. <span class="hlt">Electron</span> cross-field <span class="hlt">transport</span> in a 2.6 cm miniaturized cylindrical Hall thruster (100 W power level) has been studied through the analysis of experimental data and Monte Carlo simulations of <span class="hlt">electron</span> dynamics in the thruster channel. The numerical model takes into account elastic and inelastic <span class="hlt">electron</span> collisions with atoms, <span class="hlt">electron</span>-wall collisions, including secondary <span class="hlt">electron</span> emission, and Bohm diffusion. We show that in order to explain the observed discharge current, the <span class="hlt">electron</span> anomalous collision frequency {nu}{sub B} has to be on the order of the Bohm value, {nu}{sub B} {approx} {omega}{sub c}/16. The contribution of <span class="hlt">electron</span>-wall collisions to cross-field <span class="hlt">transport</span> is found to be insignificant.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/9469','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/9469"><span id="translatedtitle">The Role of <span class="hlt">Electron</span> <span class="hlt">Transport</span> and Trapping in MOS Total-Dose Modeling</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Fleetwood, D.M.; Winokur, P.S.; Riewe, L.C.; Flament, O.; Paillet, P.; Leray, J.L.</p> <p>1999-07-19</p> <p>Radiation-induced hole and <span class="hlt">electron</span> <span class="hlt">transport</span> and trapping are fundamental to MOS total-dose models. Here we separate the effects of <span class="hlt">electron</span>-hole annihilation and <span class="hlt">electron</span> trapping on the neutralization of radiation-induced charge during switched-bias irradiation for hard and soft oxides, via combined thermally stimulated current (TSC) and capacitance-voltage measurements. We also show that present total-dose models cannot account for the thermal stability of deeply trapped <span class="hlt">electrons</span> near the Si/SiO{sub 2} interface, or the inability of <span class="hlt">electrons</span> in deep or shallow traps to contribute to TSC at positive bias following (1) room-temperature, (2) high-temperature, or (3) switched-bias irradiation. These results require revisions of modeling parameters and boundary conditions for hole and <span class="hlt">electron</span> <span class="hlt">transport</span> in SiO{sub 2}. The nature of deep and shallow <span class="hlt">electron</span> traps in the near-interfacial SiO{sub 2} is discussed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/1061446','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/1061446"><span id="translatedtitle"><span class="hlt">Electron</span> Beam <span class="hlt">Transport</span> in Advanced Plasma Wave Accelerators</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Williams, Ronald L</p> <p>2013-01-31</p> <p>The primary goal of this grant was to develop a diagnostic for relativistic plasma wave accelerators based on injecting a low energy <span class="hlt">electron</span> beam (5-50keV) perpendicular to the plasma wave and observing the distortion of the <span class="hlt">electron</span> beam's cross section due to the plasma wave's electrostatic fields. The amount of distortion would be proportional to the plasma wave amplitude, and is the basis for the diagnostic. The beat-wave scheme for producing plasma waves, using two CO2 laser beam, was modeled using a leap-frog integration scheme to solve the equations of motion. Single <span class="hlt">electron</span> trajectories and corresponding phase space diagrams were generated in order to study and understand the details of the interaction dynamics. The <span class="hlt">electron</span> beam was simulated by combining thousands of single <span class="hlt">electrons</span>, whose initial positions and momenta were selected by random number generators. The model was extended by including the interactions of the <span class="hlt">electrons</span> with the CO2 laser fields of the beat wave, superimposed with the plasma wave fields. The results of the model were used to guide the design and construction of a small laboratory experiment that may be used to test the diagnostic idea.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/28258337','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/28258337"><span id="translatedtitle"><span class="hlt">Electronic</span> Gaming Machine (EGM) <span class="hlt">Environments</span>: Market Segments and Risk.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Rockloff, Matthew; Moskovsky, Neda; Thorne, Hannah; Browne, Matthew; Bryden, Gabrielle</p> <p>2017-03-03</p> <p>This study used a marketing-research paradigm to explore gamblers' attraction to EGMs based on different elements of the <span class="hlt">environment</span>. A select set of environmental features was sourced from a prior study (Thorne et al. in J Gambl Issues 2016b), and a discrete choice experiment was conducted through an online survey. Using the same dataset first described by Rockloff et al. (EGM <span class="hlt">Environments</span> that contribute to excess consumption and harm, 2015), a sample of 245 EGM gamblers were sourced from clubs in Victoria, Australia, and 7516 gamblers from an Australian national online survey-panel. Participants' choices amongst sets of hypothetical gambling <span class="hlt">environments</span> allowed for an estimation of the implied individual-level utilities for each feature (e.g., general sounds, location, etc.). K-means clustering on these utilities identified four unique market segments for EGM gambling, representing four different types of consumers. The segments were named according to their dominant features: Social, Value, High Roller and Internet. We found that the <span class="hlt">environments</span> orientated towards the Social and Value segments were most conducive to attracting players with relatively few gambling problems, while the High Roller and Internet-focused <span class="hlt">environments</span> had greater appeal for players with problems and vulnerabilities. This study has generated new insights into the kinds of gambling <span class="hlt">environments</span> that are most consistent with safe play.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017PPCF...59d4012N','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017PPCF...59d4012N"><span id="translatedtitle">Effects of toroidal rotation on <span class="hlt">electron</span> heat <span class="hlt">transport</span> via changes in inertial force and impurity density</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Narita, E.; Honda, M.; Yoshida, M.; Hayashi, N.; Urano, H.; Ide, S.</p> <p>2017-04-01</p> <p>Two types of JT-60U discharges are studied with an emphasis on toroidal rotation: in one discharge, which is characterized by the existence of an internal <span class="hlt">transport</span> barrier (ITB), <span class="hlt">electron</span> heat <span class="hlt">transport</span> in the core region is affected by the toroidal rotation direction, while in the other discharge, which is a conventional H-mode plasma without an ITB, the clear correlation between the toroidal rotation direction and <span class="hlt">electron</span> heat <span class="hlt">transport</span> is not observed. In both discharges, the impurity density is also found to vary together with the rotation velocity profile. With a flux-tube gyrokinetic code, we have found that the effects of the changes in the rotation velocity profile and the impurity density on <span class="hlt">electron</span> heat <span class="hlt">transport</span> are different between these discharges. Including the effects explains the tendency observed in the experiments. First, regarding the rotation velocity profile, which influences heat <span class="hlt">transport</span> through the inertial force, the dependence of heat <span class="hlt">transport</span> on the rotation direction changes, according to the gradient of the rotation velocity. Next, an increase in the impurity density stabilizes the ion temperature gradient mode, but can destabilize the trapped <span class="hlt">electron</span> mode. Therefore, it is found that the difference in the impact of the impurity density on <span class="hlt">electron</span> heat <span class="hlt">transport</span> in these discharges can be attributed to the difference in the dominant instability.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014JCHyd.164..125H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014JCHyd.164..125H"><span id="translatedtitle">Measurement and modeling of phosphorous <span class="hlt">transport</span> in shallow groundwater <span class="hlt">environments</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hendricks, G. S.; Shukla, S.; Obreza, T. A.; Harris, W. G.</p> <p>2014-08-01</p> <p>Leaching of phosphorus (P) from agricultural soils, especially those that are sandy, is adversely impacting P-limited ecosystems like Florida's Everglades. A more developed understanding of P and water management strategies and their effects on P leaching is needed to achieve reductions in subsurface P losses, especially from intensively managed dual cropping systems under plastic mulch in shallow water regions. We compared the effects of conservation P and water management strategies with traditional practices on P <span class="hlt">transport</span> to groundwater. A 3-year experiment was conducted on hydrologically isolated plots with plastic-mulched successive cropping systems to compare high (HEI) and soil test based recommended (REI) external input (water and fertilizer P) systems with traditional sub-irrigation (seepage), and REI with a potential water conservation subsurface drip irrigation system (REI-SD) with regard to groundwater P concentrations above and below the low conductivity spodic horizon (Bh). The REI treatments had higher available storage for rainfall and P than HEI. Use of both REI systems (REI = 2098 μg/L and REI-SD = 2048 μg/L) reduced groundwater P concentrations above the Bh horizon by 33% compared to HEI (3090 μg/L), and results were significant at the 0.05 level. Although the subsurface drip system saved water, it did not offer any groundwater quality (P) benefit. Mixing and dilution of influent P below the low conductivity Bh horizon between treatments and with the regional groundwater system resulted in no significant differences in groundwater P concentration below the Bh horizon. Groundwater P concentrations from this study were higher than reported elsewhere due to low soil P storage capacity (SPSC), high hydraulic conductivity of sandy soils, and a high water table beneath crop beds. The HEI system leached more P due to ferilizer P in excess of SPSC and used higher irrigation volumes compared with REI systems. Despite a 40% difference in the average</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/24981965','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/24981965"><span id="translatedtitle">Measurement and modeling of phosphorous <span class="hlt">transport</span> in shallow groundwater <span class="hlt">environments</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Hendricks, G S; Shukla, S; Obreza, T A; Harris, W G</p> <p>2014-08-01</p> <p>Leaching of phosphorus (P) from agricultural soils, especially those that are sandy, is adversely impacting P-limited ecosystems like Florida's Everglades. A more developed understanding of P and water management strategies and their effects on P leaching is needed to achieve reductions in subsurface P losses, especially from intensively managed dual cropping systems under plastic mulch in shallow water regions. We compared the effects of conservation P and water management strategies with traditional practices on P <span class="hlt">transport</span> to groundwater. A 3-year experiment was conducted on hydrologically isolated plots with plastic-mulched successive cropping systems to compare high (HEI) and soil test based recommended (REI) external input (water and fertilizer P) systems with traditional sub-irrigation (seepage), and REI with a potential water conservation subsurface drip irrigation system (REI-SD) with regard to groundwater P concentrations above and below the low conductivity spodic horizon (Bh). The REI treatments had higher available storage for rainfall and P than HEI. Use of both REI systems (REI=2098μg/L and REI-SD=2048μg/L) reduced groundwater P concentrations above the Bh horizon by 33% compared to HEI (3090μg/L), and results were significant at the 0.05 level. Although the subsurface drip system saved water, it did not offer any groundwater quality (P) benefit. Mixing and dilution of influent P below the low conductivity Bh horizon between treatments and with the regional groundwater system resulted in no significant differences in groundwater P concentration below the Bh horizon. Groundwater P concentrations from this study were higher than reported elsewhere due to low soil P storage capacity (SPSC), high hydraulic conductivity of sandy soils, and a high water table beneath crop beds. The HEI system leached more P due to ferilizer P in excess of SPSC and used higher irrigation volumes compared with REI systems. Despite a 40% difference in the average amount of</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/22269300','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/22269300"><span id="translatedtitle">Study of <span class="hlt">transport</span> properties with relativistic ponderomotive effect in two-<span class="hlt">electron</span> temperature plasma</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Sen, Sonu Dubey, A.; Varshney, Meenu Asthana; Varshney, Dinesh</p> <p>2014-04-24</p> <p>In the present paper we make an analytical investigation to study <span class="hlt">transport</span> properties with relativistic ponderomotive effect in two-<span class="hlt">electron</span> temperature plasma. Using fluid model the two-<span class="hlt">electron</span> temperature are introduced through relativistic ponderomotive force for the <span class="hlt">transportation</span> of two species of <span class="hlt">electrons</span>. Applying WKB and paraxial ray approximation the nonlinear dielectric constant and self-focusing equation is evaluated and analyzed with experimental relevance. Numerical calculations are made for different concentration of <span class="hlt">electron</span> density (10{sup 19}−10{sup 21} per cm{sup 3}) at arbitrary values of laser intensity in the range 10{sup 18}−10{sup 21} W/cm{sup 2}. For a minimum radius depending on the initial conditions it is oscillating between a minimum and maximum value. The hot <span class="hlt">electrons</span> leading to the increase of the on-axis <span class="hlt">transportation</span> and favorable effect on relativistic self-focusing.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015EL....11167002B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015EL....11167002B"><span id="translatedtitle">Effect of surface functionalization on the <span class="hlt">electronic</span> <span class="hlt">transport</span> properties of Ti3C2 MXene</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Berdiyorov, G. R.</p> <p>2015-09-01</p> <p>The effects of surface functionalization on the <span class="hlt">electronic</span> <span class="hlt">transport</span> properties of the MXene compound Ti3C2 are studied using density-functional theory in combination with the nonequilibrium Green's function formalism. Fluorinated, oxidized and hydroxylated surfaces are considered and the obtained results are compared with the ones for the pristine MXene. It is found that the surface termination has a considerable impact on the <span class="hlt">electronic</span> <span class="hlt">transport</span> in MXene. For example, the fluorinated sample shows the largest transmission, whereas surface oxidation results in a considerable reduction of the <span class="hlt">electronic</span> transmission. The current in the former sample can be up to 4 times larger for a given bias voltage as compared to the case of bare MXene. The increased transmission originates from the extended <span class="hlt">electronic</span> states and smaller variations of the electrostatic potential profile. Our findings can be useful in designing MXene-based anode materials for energy storage applications, where enhanced <span class="hlt">electronic</span> <span class="hlt">transport</span> will be an asset.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.gpo.gov/fdsys/pkg/FR-2012-08-09/pdf/2012-19584.pdf','FEDREG'); return false;" href="https://www.gpo.gov/fdsys/pkg/FR-2012-08-09/pdf/2012-19584.pdf"><span id="translatedtitle">77 FR 47692 - Notice of <span class="hlt">Transportation</span> Services' Transition From Paper to <span class="hlt">Electronic</span> Fare Media Comments...</span></a></p> <p><a target="_blank" href="http://www.gpo.gov/fdsys/browse/collection.action?collectionCode=FR">Federal Register 2010, 2011, 2012, 2013, 2014</a></p> <p></p> <p>2012-08-09</p> <p>... Office of the Secretary of <span class="hlt">Transportation</span> Notice of <span class="hlt">Transportation</span> Services' Transition From Paper to... transitioning, or have already transitioned, to <span class="hlt">electronic</span> fare media, compelling the shift from a paper based... participating Federal employees via a paper voucher process. In addition to a growing number of...</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li class="active"><span>20</span></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_20 --> <div id="page_21" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li class="active"><span>21</span></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="401"> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/10814822','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/10814822"><span id="translatedtitle">Plastid gene expression is not associated with midday depression in CO(2) assimilation and <span class="hlt">electron</span> <span class="hlt">transport</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Trivedi; Reddy; Sane</p> <p>2000-06-29</p> <p>To investigate the effect of diurnal variations on chloroplastic <span class="hlt">electron</span> <span class="hlt">transport</span> as well as accumulation of gene products associated with it, studies were carried out on Populus deltoides, a tree species. <span class="hlt">Electron</span> <span class="hlt">transport</span> studies showed two peak responses as a large diurnal change with pronounced midday depression in whole chain (H(2)O--> MV) as well as partial reactions for PSII (H(2)O-->PBQ) and PSI (DCPIP-->MV). The <span class="hlt">electron</span> <span class="hlt">transport</span> rates first increased from 05:00 h to a maximum at around 09:00 h and then showed a decrease at 13:00 h followed by recovery and further decrease. The pigments associated with <span class="hlt">electron</span> <span class="hlt">transport</span> chain did not show any change during the day. Surprisingly midday depression in the accumulation of transcripts and polypeptides related to <span class="hlt">electron</span> <span class="hlt">transport</span> was not observed. This suggests that chloroplastic gene expression is not associated with the midday depression observed for both CO(2) assimilation and <span class="hlt">electron</span> <span class="hlt">transport</span>. Studies on the transcripts of psbD/C operon during the day showed that there were differences in the processing pattern although the steady state levels of the processed transcripts of this operon did not show any variation.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016Nanot..27z5706H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016Nanot..27z5706H"><span id="translatedtitle">Strain-modulated <span class="hlt">electronic</span> and thermal <span class="hlt">transport</span> properties of two-dimensional O-silica</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Han, Yang; Qin, Guangzhao; Jungemann, Christoph; Hu, Ming</p> <p>2016-07-01</p> <p>Silica is one of the most abundant materials in the Earth’s crust and is a remarkably versatile and important engineering material in various modern science and technology. Recently, freestanding and well-ordered two-dimensional (2D) silica monolayers with octahedral (O-silica) building blocks were found to be theoretically stable by (Wang G et al 2015 J. Phys. Chem. C 119 15654-60). In this paper, by performing first-principles calculations, we systematically investigated the <span class="hlt">electronic</span> and thermal <span class="hlt">transport</span> properties of 2D O-silica and also studied how these properties can be tuned by simple mechanical stretching. Unstrained 2D O-silica is an insulator with an indirect band gap of 6.536 eV. The band gap decreases considerably with bilateral strain up to 29%, at which point a semiconductor-metal transition occurs. More importantly, the in-plane thermal conductivity of freestanding 2D O-silica is found to be unusually high, which is around 40 to 50 times higher than that of bulk α-quartz and more than two orders of magnitude higher than that of amorphous silica. The thermal conductivity of O-silica decreases by almost two orders of magnitude when the bilateral stretching strain reaches 10%. By analyzing the mode-dependent phonon properties and phonon-scattering channel, the phonon lifetime is found to be the dominant factor that leads to the dramatic decrease of the lattice thermal conductivity under strain. The very sensitive response of both band gap and phonon <span class="hlt">transport</span> properties to the external mechanical strain will enable 2D O-silica to easily adapt to the different <span class="hlt">environment</span> of realistic applications. Our study is expected to stimulate experimental exploration of further physical and chemical properties of 2D silica systems, and offers perspectives on modulating the <span class="hlt">electronic</span> and thermal properties of related low-dimensional structures for applications such as thermoelectric, photovoltaic, and optoelectronic devices.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/21403192','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/21403192"><span id="translatedtitle">The effect of magnetic field and disorders on the <span class="hlt">electronic</span> <span class="hlt">transport</span> in graphene nanoribbons.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Kumar, S Bala; Jalil, M B A; Tan, S G; Liang, Gengchiau</p> <p>2010-09-22</p> <p>We developed a unified mesoscopic <span class="hlt">transport</span> model for graphene nanoribbons, which combines the nonequilibrium Green's function (NEGF) formalism with the real-space π-orbital model. Based on this model, we probe the spatial distribution of <span class="hlt">electrons</span> under a magnetic field, in order to obtain insights into the various signature Hall effects in disordered armchair graphene nanoribbons (AGNR). In the presence of a uniform perpendicular magnetic field (B[Symbol: see text]-field), a perfect AGNR shows three distinct spatial current profiles at equilibrium, depending on its width. Under nonequilibrium conditions (i.e. in the presence of an applied bias), the net <span class="hlt">electron</span> flow is restricted to the edges and occurs in opposite directions depending on whether the Fermi level lies within the valence or conduction band. For <span class="hlt">electrons</span> at an energy level below the conduction window, the B[Symbol: see text]-field gives rise to local <span class="hlt">electron</span> flux circulation, although the global flux is zero. Our study also reveals the suppression of <span class="hlt">electron</span> backscattering as a result of the edge <span class="hlt">transport</span> which is induced by the B[Symbol: see text]-field. This phenomenon can potentially mitigate the undesired effects of disorder, such as bulk and edge vacancies, on the <span class="hlt">transport</span> properties of AGNR. Lastly, we show that the effect of [Formula: see text]-field on <span class="hlt">electronic</span> <span class="hlt">transport</span> is less significant in the multimode compared to the single-mode <span class="hlt">electron</span> <span class="hlt">transport</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017JChPh.146j4306O','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017JChPh.146j4306O"><span id="translatedtitle">Predicting <span class="hlt">transport</span> regime and local electrostatic <span class="hlt">environment</span> from Coulomb blockade diamond sizes</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Olsen, Stine T.; Hansen, Thorsten; Mikkelsen, Kurt V.</p> <p>2017-03-01</p> <p><span class="hlt">Electron</span> <span class="hlt">transport</span> through a molecule is often described in one of the two regimes: the coherent tunnelling regime or the Coulomb blockade regime. The twilight zone of the two regimes still possesses many unsolved questions. A theoretical analysis of the oligophenylenevinylene OPV3 experiments by Bjørnholm and co-workers is performed. The experiments showed how two OPV3 derivatives performed very differently despite the strong similarity of the molecular structure, hence the experimental data showed two different <span class="hlt">transport</span> mechanisms. The different <span class="hlt">transport</span> mechanisms of the two OPV3 derivatives are explained from quantum mechanical calculations of the molecular redox energies and from the experimentally accessible window size.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/22490523','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/22490523"><span id="translatedtitle">Opto-<span class="hlt">electronic</span> <span class="hlt">transport</span> properties of graphene oxide based devices</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Das, Poulomi; Ibrahim, Sk; Pal, Tanusri; Chakraborty, Koushik; Ghosh, Surajit</p> <p>2015-06-24</p> <p>Large area, solution-processed, graphene oxide (GO)nanocomposite based photo FET has been successfully fabricated. The device exhibits p-type charge <span class="hlt">transport</span> characteristics in dark condition. Our measurements indicate that the <span class="hlt">transport</span> characteristics are gate dependent and extremely sensitive to solar light. Photo current decay mechanism of GO is well explained and is associated with two phenomena: a) fast response process and b) slow response process. Slow response photo decay can be considered as the intrinsic phenomena which are present for both GO and reduced GO (r-GO), whereas the first response photo decay is controlled by the surface defect states. Demonstration of photo FET performance of GO thin film is a significant step forward in integrating these devices in various optoelectronic circuits.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/22955881','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/22955881"><span id="translatedtitle">Long-range <span class="hlt">electron</span> <span class="hlt">transport</span> in Geobacter sulfurreducens biofilms is redox gradient-driven.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Snider, Rachel M; Strycharz-Glaven, Sarah M; Tsoi, Stanislav D; Erickson, Jeffrey S; Tender, Leonard M</p> <p>2012-09-18</p> <p>Geobacter spp. can acquire energy by coupling intracellular oxidation of organic matter with extracellular <span class="hlt">electron</span> transfer to an anode (an electrode poised at a metabolically oxidizing potential), forming a biofilm extending many cell lengths away from the anode surface. It has been proposed that long-range <span class="hlt">electron</span> <span class="hlt">transport</span> in such biofilms occurs through a network of bound redox cofactors, thought to involve extracellular matrix c-type cytochromes, as occurs for polymers containing discrete redox moieties. Here, we report measurements of <span class="hlt">electron</span> <span class="hlt">transport</span> in actively respiring Geobacter sulfurreducens wild type biofilms using interdigitated microelectrode arrays. Measurements when one electrode is used as an anode and the other electrode is used to monitor redox status of the biofilm 15 μm away indicate the presence of an intrabiofilm redox gradient, in which the concentration of <span class="hlt">electrons</span> residing within the proposed redox cofactor network is higher farther from the anode surface. The magnitude of the redox gradient seems to correlate with current, which is consistent with <span class="hlt">electron</span> <span class="hlt">transport</span> from cells in the biofilm to the anode, where <span class="hlt">electrons</span> effectively diffuse from areas of high to low concentration, hopping between redox cofactors. Comparison with gate measurements, when one electrode is used as an <span class="hlt">electron</span> source and the other electrode is used as an <span class="hlt">electron</span> drain, suggests that there are multiple types of redox cofactors in Geobacter biofilms spanning a range in oxidation potential that can engage in <span class="hlt">electron</span> <span class="hlt">transport</span>. The majority of these redox cofactors, however, seem to have oxidation potentials too negative to be involved in <span class="hlt">electron</span> <span class="hlt">transport</span> when acetate is the <span class="hlt">electron</span> source.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.dtic.mil/docs/citations/ADA234597','DTIC-ST'); return false;" href="http://www.dtic.mil/docs/citations/ADA234597"><span id="translatedtitle"><span class="hlt">Electronic</span> and Ionic <span class="hlt">Transport</span> in Processable Conducting Polymers</span></a></p> <p><a target="_blank" href="https://publicaccess.dtic.mil/psm/api/service/search/search">DTIC Science & Technology</a></p> <p></p> <p>1991-04-12</p> <p>Reynolds, J. R. "Charge and Ion <span class="hlt">Transport</span> in Poly(pyrrole copper phthalocyanine - sulfonate ) During Redox Switching," J. Electroanal. Chem., submitted...the following polymers: (1) copolymers of heterocyclic rings such as pyrrole or furan with disubstituted ( methyl or methoxy groups ) benzene; (2...SUBJECT TERMS (Continue on reverse if necessary and identify by block number) FIEL GRUP I SUB- GROUP IPoly[1,4-bis(2-furanyl)-2,5-disubstituted-p</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.dtic.mil/docs/citations/ADA260122','DTIC-ST'); return false;" href="http://www.dtic.mil/docs/citations/ADA260122"><span id="translatedtitle">Simulation of <span class="hlt">Electronic</span> <span class="hlt">Transport</span> in Semiconductor Heterolayer Devices</span></a></p> <p><a target="_blank" href="https://publicaccess.dtic.mil/psm/api/service/search/search">DTIC Science & Technology</a></p> <p></p> <p>1992-10-01</p> <p>Mesoscopic Systems With Open Boundaries Using the Multidimensional Time - Dependent Schr • dinger Equation ," J. Appl. Phys. 69 (10), pp. 7153-7158 (1991...Conference on Computational Physics, University of Colorado at Boulder, Boulder, Colorado, June 11-15, 1990. " Approaches to <span class="hlt">Transport</span> in Semiconductor...Work in the three years of the grant was aimed at both improving and generalizing the full band Monte Carlo approach and at developing numerical</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/6984569','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/6984569"><span id="translatedtitle">Adjoint <span class="hlt">transport</span> calculations for sensitivity analysis of the Hiroshima air-over-ground <span class="hlt">environment</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Broadhead, B.L.; Cacuci, D.G.; Pace, J.V. III</p> <p>1984-01-01</p> <p>A major effort within the US Dose Reassessment Program is aimed at recalculating the <span class="hlt">transport</span> of initial nuclear radiation in an air-over-ground <span class="hlt">environment</span>. This paper is the first report of results from adjoint calculations in the Hiroshima air-over-ground <span class="hlt">environment</span>. The calculations use a Hiroshima/Nagasaki multi-element ground, ENDF/B-V nuclear data, one-dimensional ANISN flux weighting for neutron and gamma cross sections, a source obtained by two-dimensional hydrodynamic and three-dimensional <span class="hlt">transport</span> calculations, and best-estimate atmospheric conditions from Japanese sources. 7 references, 2 figures.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://eric.ed.gov/?q=Nakamoto&pg=2&id=EJ396892','ERIC'); return false;" href="http://eric.ed.gov/?q=Nakamoto&pg=2&id=EJ396892"><span id="translatedtitle">Technical and Social <span class="hlt">Environments</span> of <span class="hlt">Electronic</span> Publishing in Japan.</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Nakamoto, Hideshiro</p> <p>1988-01-01</p> <p>Discusses the feasibility of introducing <span class="hlt">electronic</span> publishing into traditional Japanese markets within the context of recent progress in other technologies and mass communications in that country. It is suggested that the content and quality of publications, rather than the media by which they are presented, will determine the acceptance of…</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://files.eric.ed.gov/fulltext/ED134221.pdf','ERIC'); return false;" href="http://files.eric.ed.gov/fulltext/ED134221.pdf"><span id="translatedtitle">Reactive Learning <span class="hlt">Environment</span> for Computer Assisted <span class="hlt">Electronics</span> Instruction.</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Brown, John Seely; And Others</p> <p></p> <p>This report describes the development of several new computer based strategies for teaching troubleshooting principles to <span class="hlt">electronics</span> technicians. The computer programs to implement these strategies were developed in part from software produced in previous contracts. The report documents an experiment in which those materials were presented to…</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20060044324&hterms=digital+electronics&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D60%26Ntt%3Ddigital%2Belectronics','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20060044324&hterms=digital+electronics&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D60%26Ntt%3Ddigital%2Belectronics"><span id="translatedtitle">Re-configurable <span class="hlt">electronics</span> behavoir under extreme thermal <span class="hlt">environment</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Stoica, Adrian; Lacayo, Veronica; Rajeshuni, Ramesham; Keymeulen, Didier; Zebulum, Ricardo; Neff, Joe; Burke, Gary; Daud, Taher</p> <p>2005-01-01</p> <p>This paper focuses on analog/digital <span class="hlt">electronics</span> at low-temperatures. The experiments cover separate tests of the whole Evolvable Hardware system: the Evolutionary Processor (the DSP in the SABLE system), Xilinx Virtes II Pro FPGA evaluation board, and the Reconfigurable analog array components tested at low and high temperatures.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/7028060','DOE-PATENT-XML'); return false;" href="http://www.osti.gov/scitech/biblio/7028060"><span id="translatedtitle"><span class="hlt">Electronically</span> conductive ceramics for high temperature oxidizing <span class="hlt">environments</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/doepatents">DOEpatents</a></p> <p>Kucera, G.H.; Smith, J.L.; Sim, J.W.</p> <p>1983-11-10</p> <p>This invention pertains to a high temperature, ceramic composition having <span class="hlt">electronic</span> conductivity as measured by resistivity below about 500 ohm-cm, chemical stability particularly with respect to cathode conditions in a molten carbonate fuel cell, and composed of an alkali metal, transition metal oxide containing a dopant metal in the crystalline structure to replace a portion of the alkali metal or transition metal.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/865739','DOE-PATENT-XML'); return false;" href="http://www.osti.gov/scitech/servlets/purl/865739"><span id="translatedtitle"><span class="hlt">Electronically</span> conductive ceramics for high temperature oxidizing <span class="hlt">environments</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/doepatents">DOEpatents</a></p> <p>Kucera, Gene H.; Smith, James L.; Sim, James W.</p> <p>1986-01-01</p> <p>A high temperature, ceramic composition having <span class="hlt">electronic</span> conductivity as measured by resistivity below about 500 ohm-cm, chemical stability particularly with respect to cathode conditions in a molten carbonate fuel cell, and composed of an alkali metal, transition metal oxide containing a dopant metal in the crystalline structure to replace a portion of the alkali metal or transition metal.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4139731','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4139731"><span id="translatedtitle">Natural occurrence of microbial sulphur oxidation by long-range <span class="hlt">electron</span> <span class="hlt">transport</span> in the seafloor</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Malkin, Sairah Y; Rao, Alexandra MF; Seitaj, Dorina; Vasquez-Cardenas, Diana; Zetsche, Eva-Maria; Hidalgo-Martinez, Silvia; Boschker, Henricus TS; Meysman, Filip JR</p> <p>2014-01-01</p> <p>Recently, a novel mode of sulphur oxidation was described in marine sediments, in which sulphide oxidation in deeper anoxic layers was electrically coupled to oxygen reduction at the sediment surface. Subsequent experimental evidence identified that long filamentous bacteria belonging to the family Desulfobulbaceae likely mediated the <span class="hlt">electron</span> <span class="hlt">transport</span> across the centimetre-scale distances. Such long-range <span class="hlt">electron</span> transfer challenges some long-held views in microbial ecology and could have profound implications for sulphur cycling in marine sediments. But, so far, this process of electrogenic sulphur oxidation has been documented only in laboratory experiments and so its imprint on the seafloor remains unknown. Here we show that the geochemical signature of electrogenic sulphur oxidation occurs in a variety of coastal sediment <span class="hlt">environments</span>, including a salt marsh, a seasonally hypoxic basin, and a subtidal coastal mud plain. In all cases, electrogenic sulphur oxidation was detected together with an abundance of Desulfobulbaceae filaments. Complementary laboratory experiments in intertidal sands demonstrated that mechanical disturbance by bioturbating fauna destroys the electrogenic sulphur oxidation signal. A survey of published geochemical data and 16S rRNA gene sequences identified that electrogenic sulphide oxidation is likely present in a variety of marine sediments with high sulphide generation and restricted bioturbation, such as mangrove swamps, aquaculture areas, seasonally hypoxic basins, cold sulphide seeps and possibly hydrothermal vent <span class="hlt">environments</span>. This study shows for the first time that electrogenic sulphur oxidation occurs in a wide range of marine sediments and that bioturbation may exert a dominant control on its natural distribution. PMID:24671086</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20080020515','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20080020515"><span id="translatedtitle">Lunar Dust Charging by Secondary <span class="hlt">Electron</span> Emission and its Complex Role in the Lunar <span class="hlt">Environment</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Abbas, M. M.; Tankosic, D.; Spann, J. F.; LeClair, A.; Dube, M. J.</p> <p>2008-01-01</p> <p>The lunar surface is covered with a thick layer of micron/sub-micron size dust grains formed by billions of years of meteoritic impact. With virtually no atmosphere and exposed to the solar wind plasma and solar electromagnetic radiation, the lunar surface and the dust grains are electrostatically charged. The dominant charging processes include: photoelectric emissions (UV, X-rays), impact of solar wind <span class="hlt">electrons</span> and ions, and secondary <span class="hlt">electron</span> emissions (SEE) induced by energetic solar wind <span class="hlt">electrons</span>. During the Apollo missions, the astronauts found the lunar dust to be extraordinarily high in its adhesive characteristics, sticking to the suits and the mechanical equipment. Electrostatically charged lunar dust is believed to be <span class="hlt">transported</span> over long distances by the induced electric fields, as indicated by the observed dust streamers and the horizon glow [e.g., 1-3]. The hazardous effects of dust in the lunar <span class="hlt">environment</span> are recognized to be one of the major issues that must be addressed in planning the forthcoming missions for robotic and human exploration of the Moon. Theoretical studies are being performed along with the development of analytical models and a variety of experimental investigations, to better understand the lunar dust phenomena. [e.g., 4-6]. The lunar dust is believed to be charged negatively on the lunar night-side by interaction With solar wind <span class="hlt">electrons</span>. However, rigorous theoretical expressions for calculation of SEE yields and the sticking efficiencies of individual micron size dust grains are not yet available, and the information has to be obtained by experiment. On theoretical considerations, however, it is well recognized that SEE yields, similar to the photoelectric yields for small-size grains, would be totally different from the corresponding bulk values [e.g., 7-9]. Some theoretical models for charging of individual small spherical particles have been developed [e.g., 10], and some limited measurements on individual metallic dust</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2002AAS...200.4904L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2002AAS...200.4904L"><span id="translatedtitle">Radio Studies of <span class="hlt">Electron</span> Acceleration and <span class="hlt">Transport</span> During Solar Flares</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Lee, J.</p> <p>2002-05-01</p> <p>At centimeter wavelengths solar flare radiation is dominated by incoherent gyrosynchrotron emissions from 10 keV to several MeV <span class="hlt">electrons</span>. Due to unique sensitivity of the gyrosynchrotron radiation to <span class="hlt">electron</span> momentum distribution and ambient magnetic field, the radio observations at these wavelengths can provide important clues to the evolution of high-energy <span class="hlt">electrons</span> residing in the flaring loops. In this talk I review some of recent progress made primarily using the Owens Valley Solar Array (OVSA) to understand acceleration, trapping, and precipitation of <span class="hlt">electrons</span> during solar flares. These works are extensions of the traditional, correlative studies of temporal and spatial morphologies of radio bursts versus those of other flare radiations (X-rays, UV/EUV, and Hα ) to exploit the multi-frequencies of the OVSA. The results demonstrate additional advantages of radio observations as a flare diagnostic tool when both spatial and spectral resolutions are available, and provide a major initiative in building the Frequency-Agile Radio Telescope (FASR). This work has been supported by NASA grant NAG5-10891. The OVSA is supported by NSF grant AST-9987366 to New Jersey Institute of Technology.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/22413317','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/22413317"><span id="translatedtitle"><span class="hlt">Electron</span> transfer activation of a second water channel for proton <span class="hlt">transport</span> in [FeFe]-hydrogenase</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Sode, Olaseni; Voth, Gregory A.</p> <p>2014-12-14</p> <p>Hydrogenase enzymes are important because they can reversibly catalyze the production of molecular hydrogen. Proton <span class="hlt">transport</span> mechanisms have been previously studied in residue pathways that lead to the active site of the enzyme via residues Cys299 and Ser319. The importance of this pathway and these residues has been previously exhibited through site-specific mutations, which were shown to interrupt the enzyme activity. It has been shown recently that a separate water channel (WC2) is coupled with <span class="hlt">electron</span> <span class="hlt">transport</span> to the active site of the [FeFe]-hydrogenase. The water-mediated proton <span class="hlt">transport</span> mechanisms of the enzyme in different <span class="hlt">electronic</span> states have been studied using the multistate empirical valence bond reactive molecular dynamics method, in order to understand any role WC2 may have in facilitating the residue pathway in bringing an additional proton to the enzyme active site. In a single <span class="hlt">electronic</span> state A{sup 2−}, a water wire was formed through which protons can be <span class="hlt">transported</span> with a low free energy barrier. The remaining <span class="hlt">electronic</span> states were shown, however, to be highly unfavorable to proton <span class="hlt">transport</span> in WC2. A double amino acid substitution is predicted to obstruct proton <span class="hlt">transport</span> in <span class="hlt">electronic</span> state A{sup 2-} by closing a cavity that could otherwise fill with water near the proximal Fe of the active site.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/22492756','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/22492756"><span id="translatedtitle"><span class="hlt">Electronic</span> <span class="hlt">transport</span> characterization of silicon wafers by spatially resolved steady-state photocarrier radiometric imaging</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Wang, Qian; Li, Bincheng</p> <p>2015-09-28</p> <p>Spatially resolved steady-state photocarrier radiometric (PCR) imaging technique is developed to characterize the <span class="hlt">electronic</span> <span class="hlt">transport</span> properties of silicon wafers. Based on a nonlinear PCR theory, simulations are performed to investigate the effects of <span class="hlt">electronic</span> <span class="hlt">transport</span> parameters (the carrier lifetime, the carrier diffusion coefficient, and the front surface recombination velocity) on the steady-state PCR intensity profiles. The <span class="hlt">electronic</span> <span class="hlt">transport</span> parameters of an n-type silicon wafer are simultaneously determined by fitting the measured steady-state PCR intensity profiles to the three-dimensional nonlinear PCR model. The determined <span class="hlt">transport</span> parameters are in good agreement with the results obtained by the conventional modulated PCR technique with multiple pump beam radii.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/22118631','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/22118631"><span id="translatedtitle">Numerical estimation on free <span class="hlt">electrons</span> generated by shielded radioactive materials under various gaseous <span class="hlt">environments</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Kim, D. S.; Lee, W. S.; So, J. H.; Choi, E. M.</p> <p>2013-06-15</p> <p>We report simulation results on generation of free <span class="hlt">electrons</span> due to the presence of radioactive materials under controlled pressure and gases using a general Monte Carlo <span class="hlt">transport</span> code (MCNPX). A radioactive material decays to lower atomic number, simultaneously producing high energy gamma rays that can generate free <span class="hlt">electrons</span> via various scattering mechanisms. This paper shows detailed simulation works for answering how many free <span class="hlt">electrons</span> can be generated under the existence of shielded radioactive materials as a function of pressure and types of gases.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li class="active"><span>21</span></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_21 --> <div id="page_22" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li class="active"><span>22</span></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li><a href="#" onclick='return showDiv("page_24");'>24</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="421"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19720010060','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19720010060"><span id="translatedtitle">Low-energy <span class="hlt">electron</span> <span class="hlt">transport</span> with the method of discrete ordinates</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Bartine, D. E.; Alsmiller, R. G., Jr.; Mynatt, F. R.; Engle, W. W., Jr.; Barish, J.</p> <p>1972-01-01</p> <p>The one-dimensional discrete ordinates code ANISN was adapted to <span class="hlt">transport</span> low energy (a few MeV) <span class="hlt">electrons</span>. Calculated results obtained with ANISN were compared with experimental data for transmitted <span class="hlt">electron</span> energy and angular distribution data for <span class="hlt">electrons</span> normally incident on aluminum slabs of various thicknesses. The calculated and experimental results are in good agreement for a thin slab (0.2 of the <span class="hlt">electron</span> range), but not for the thicker slabs (0.6 of the <span class="hlt">electron</span> range). Calculated results obtained with ANISN were also compared with results obtained using Monte Carlo methods.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/22472123','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/22472123"><span id="translatedtitle">Kinetics of vertical <span class="hlt">transport</span> and localization of <span class="hlt">electrons</span> in strained semiconductor supperlattices</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Gerchikov, L. G. Mamaev, Yu. A.; Yashin, Yu. P.</p> <p>2015-08-15</p> <p>The kinetics of vertical <span class="hlt">electron</span> <span class="hlt">transport</span> in a semiconductor superlattice is considered taking into account partial localization of <span class="hlt">electrons</span>. The time dependences of photoemission currents from samples based on a strained semiconductor superlattice calculated by numerically solving the kinetic equation are in good agreement with experimental data. Comparison of the theory with experiment makes it possible to determine the characteristic <span class="hlt">electron</span> localization and thermoactivation times, the diffusion length, and losses of photoelectrons in the superlattice.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010PhPl...17e6101L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010PhPl...17e6101L"><span id="translatedtitle">Internal <span class="hlt">electron</span> <span class="hlt">transport</span> barrier due to neoclassical ambipolarity in the Helically Symmetric Experimenta)</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Lore, J.; Guttenfelder, W.; Briesemeister, A.; Anderson, D. T.; Anderson, F. S. B.; Deng, C. B.; Likin, K. M.; Spong, D. A.; Talmadge, J. N.; Zhai, K.</p> <p>2010-05-01</p> <p><span class="hlt">Electron</span> cyclotron heated plasmas in the Helically Symmetric Experiment (HSX) feature strongly peaked <span class="hlt">electron</span> temperature profiles; central temperatures are 2.5 keV with 100 kW injected power. These measurements, coupled with neoclassical predictions of large "<span class="hlt">electron</span> root" radial electric fields with strong radial shear, are evidence of a neoclassically driven thermal <span class="hlt">transport</span> barrier. Neoclassical <span class="hlt">transport</span> quantities are calculated using the PENTA code [D. A. Spong, Phys. Plasmas 12, 056114 (2005)], in which momentum is conserved and parallel flow is included. Unlike a conventional stellarator, which exhibits strong flow damping in all directions on a flux surface, quasisymmetric stellarators are free to rotate in the direction of symmetry, and the effect of momentum conservation in neoclassical calculations may therefore be significant. Momentum conservation is shown to modify the neoclassical ion flux and ambipolar ion root radial electric fields in the quasisymmetric configuration. The effect is much smaller in a HSX configuration where the symmetry is spoiled. In addition to neoclassical <span class="hlt">transport</span>, a model of trapped <span class="hlt">electron</span> mode turbulence is used to calculate the turbulent-driven <span class="hlt">electron</span> thermal diffusivity. Turbulent <span class="hlt">transport</span> quenching due to the neoclassically predicted radial electric field profile is needed in predictive <span class="hlt">transport</span> simulations to reproduce the peaking of the measured <span class="hlt">electron</span> temperature profile [Guttenfelder et al., Phys. Rev. Lett. 101, 215002 (2008)].</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19850014199','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19850014199"><span id="translatedtitle">Discharge characteristics of dielectric materials examined in mono-, dual-, and spectral energy <span class="hlt">electron</span> charging <span class="hlt">environments</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Coakley, P.; Treadway, M.; Wild, N.; Kitterer, B.</p> <p>1985-01-01</p> <p>The effects of midenergy <span class="hlt">electrons</span> on the charge and discharge characteristics of spacecraft dielectric materials and the data base from which basic discharge models can be formulated is expanded. Thin dielectric materials were exposed to low, mid combined low and mid, and spectral energy <span class="hlt">electron</span> <span class="hlt">environments</span>. Three important results are presented: (1) it determined <span class="hlt">electron</span> <span class="hlt">environments</span> that lead to dielectric discharges at potentials less negative than -5 kV; (2) two types of discharges were identified that dominate the kinds of discharges seen; and (3) it is shown that, for the thin dielectric materials tested, the worst-case discharges observed in the various <span class="hlt">environments</span> are similar.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014PhDT.......231L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014PhDT.......231L"><span id="translatedtitle">Nanoscale heat <span class="hlt">transport</span> via <span class="hlt">electrons</span> and phonons by molecular dynamics simulations</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Lin, Keng-Hua</p> <p></p> <p>Nanoscale heat <span class="hlt">transport</span> has become a crucial research topic due to the growing importance of nanotechnology for manufacturing, energy conversion, medicine and <span class="hlt">electronics</span>. Thermal <span class="hlt">transport</span> properties at the nanoscale are distinct from the macroscopic ones since the sizes of nanoscale features, such as free surfaces and interfaces, are comparable to the wavelengths and mean free paths of the heat carriers (<span class="hlt">electrons</span> and phonons), and lead to changes in thermal <span class="hlt">transport</span> properties. Therefore, understanding how the nanoscale features and energy exchange between the heat carriers affect thermal <span class="hlt">transport</span> characteristics are the goals of this research. Molecular dynamics (MD) is applied in this research to understand the details of nanoscale heat <span class="hlt">transport</span>. The advantage of MD is that the size effect, anharmonicity, atomistic structure, and non-equilibrium behavior of the system can all be captured since the dynamics of atoms are described explicitly in MD. However, MD neglects the thermal role of <span class="hlt">electrons</span> and therefore it is unable to describe heat <span class="hlt">transport</span> in metal or metal-semiconductor systems accurately. To address this limitation of MD, we develop a method to simulate <span class="hlt">electronic</span> heat <span class="hlt">transport</span> by implementing <span class="hlt">electronic</span> degrees of freedom to MD. In this research, nanoscale heat <span class="hlt">transport</span> in semiconductor, metal, and metal-semiconductor systems is studied. Size effects on phonon thermal <span class="hlt">transport</span> in SiGe superlattice thin films and nanowires are studied by MD. We find that, opposite to the macroscopic trend, superlattice thin films can achieve lower thermal conductivity than nanowires at small scales due to the change of phonon nature caused by adjusting the superlattice periodic length and specimen length. Effects of size and <span class="hlt">electron</span>-phonon coupling rate on thermal conductivity and thermal interface resistivity in Al and model metal-semiconductor systems are studied by MD with <span class="hlt">electronic</span> degrees of freedom. The results show that increasing the specimen</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4730679','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4730679"><span id="translatedtitle">Smart <span class="hlt">Electronic</span> Laboratory Notebooks for the NIST Research <span class="hlt">Environment</span></span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Gates, Richard S.; McLean, Mark J.; Osborn, William A.</p> <p>2015-01-01</p> <p>Laboratory notebooks have been a staple of scientific research for centuries for organizing and documenting ideas and experiments. Modern laboratories are increasingly reliant on <span class="hlt">electronic</span> data collection and analysis, so it seems inevitable that the digital revolution should come to the ordinary laboratory notebook. The most important aspect of this transition is to make the shift as comfortable and intuitive as possible, so that the creative process that is the hallmark of scientific investigation and engineering achievement is maintained, and ideally enhanced. The smart <span class="hlt">electronic</span> laboratory notebooks described in this paper represent a paradigm shift from the old pen and paper style notebooks and provide a host of powerful operational and documentation capabilities in an intuitive format that is available anywhere at any time. PMID:26958447</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/26958447','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/26958447"><span id="translatedtitle">Smart <span class="hlt">Electronic</span> Laboratory Notebooks for the NIST Research <span class="hlt">Environment</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Gates, Richard S; McLean, Mark J; Osborn, William A</p> <p>2015-01-01</p> <p>Laboratory notebooks have been a staple of scientific research for centuries for organizing and documenting ideas and experiments. Modern laboratories are increasingly reliant on <span class="hlt">electronic</span> data collection and analysis, so it seems inevitable that the digital revolution should come to the ordinary laboratory notebook. The most important aspect of this transition is to make the shift as comfortable and intuitive as possible, so that the creative process that is the hallmark of scientific investigation and engineering achievement is maintained, and ideally enhanced. The smart <span class="hlt">electronic</span> laboratory notebooks described in this paper represent a paradigm shift from the old pen and paper style notebooks and provide a host of powerful operational and documentation capabilities in an intuitive format that is available anywhere at any time.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/26167431','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/26167431"><span id="translatedtitle">Enhanced radial <span class="hlt">transport</span> and energization of radiation belt <span class="hlt">electrons</span> due to drift orbit bifurcations.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Ukhorskiy, A Y; Sitnov, M I; Millan, R M; Kress, B T; Smith, D C</p> <p>2014-01-01</p> <p>[1]Relativistic <span class="hlt">electron</span> intensities in Earth's outer radiation belt can vary by multiple orders of magnitude on the time scales ranging from minutes to days. One fundamental process contributing to dynamic variability of radiation belt intensities is the radial <span class="hlt">transport</span> of relativistic <span class="hlt">electrons</span> across their drift shells. In this paper we analyze the properties of three-dimensional radial <span class="hlt">transport</span> in a global magnetic field model driven by variations in the solar wind dynamic pressure. We use a test particle approach which captures anomalous effects such as drift orbit bifurcations. We show that the bifurcations lead to an order of magnitude increase in radial <span class="hlt">transport</span> rates and enhance the energization at large equatorial pitch angles. Even at quiet time fluctuations in dynamic pressure, radial <span class="hlt">transport</span> at large pitch angles exhibits strong deviations from the diffusion approximation. The radial <span class="hlt">transport</span> rates are much lower at small pitch angle values which results in a better agreement with the diffusion approximation.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016APS..DPPJO9009C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016APS..DPPJO9009C"><span id="translatedtitle">Role of the magnetic island and low- k turbulence on radial <span class="hlt">electron</span> heat <span class="hlt">transport</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Choi, M. J.; Park, H. K.; in, Y.; Ko, S. H.; Kim, H. S.; Bae, C.; Kwon, J. M.; Lee, W.; Lee, K. D.; Lee, H. H.; Ko, W. H.; Lee, S. H.; Lee, J. H.; Ko, J.; Kim, J.; Woo, M. H.; Jeong, M.; Park, B. H.; Yun, G. S.; Lee, J.; Kim, M.; Luhmann, N. C., Jr.</p> <p>2016-10-01</p> <p>Magnetic islands can enhance or reduce the radial <span class="hlt">transport</span> either by reconnecting field lines or producing the poloidal flow shear across the rational surface. Both cases have been observed in the KSTAR L-mode plasmas. In the first case, the temperature inside the q = 2 surface decreases severely ( 25%) with the enhanced <span class="hlt">transport</span> by the rotating m / n = 2 / 1 magnetic island. However, in the case where the 2/1 magnetic island is driven and locked by the n = 1 resonant magnetic perturbation, the <span class="hlt">transport</span> is reduced and the <span class="hlt">electron</span> temperature (Te) gradient is increased across the island with a clear poloidal flow shear. The poloidal flow shear has been identified utilizing <span class="hlt">electron</span> cyclotron emission imaging (ECEI) measurements of the low-k turbulent Te fluctuations driven by the increased Te gradient. In addition, the interaction between the Te turbulence and magnetic island causes the transient heat <span class="hlt">transport</span> events and affects the <span class="hlt">transport</span> characteristics near the q = 2 region.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19850014165','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19850014165"><span id="translatedtitle">Measured <span class="hlt">electron</span> contribution to Shuttle plasma <span class="hlt">environment</span>: Abbreviated update</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Mcmahon, W.; Salter, R.; Hills, R.; Delorey, D.</p> <p>1985-01-01</p> <p>The differential energy spectra of <span class="hlt">electrons</span> between 1 and 100 eV were measured by an <span class="hlt">electron</span> spectrometer flown on an early shuttle. This energy range was scanned in 64 incremental steps with a resolution of 7%. The most striking feature that was observed throughout these spectra was a relatively flat distribution of the higher energy <span class="hlt">electrons</span> out to 100 eV. This is in contrast to normal ambient spectra which consistently show a rapid decline in quantitative flux beyond 50 to 55 eV. The lower energy (1 to 2 eV) end of these spectra showed steep thermal trails comparable to normal ambient spectral structure. In general, daytime fluxes were significantly higher than those obtained during nighttime measurements. Quantitative flux excursions which may possibly be associated with thruster firing were frequently observed. Spectral structure suggestive of the N2 vibrational excitation energy loss mechanism was also seen in the data from some measurement periods. Examples of these spectra are shown and possible correlations are discussed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016PhRvB..93t5408R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016PhRvB..93t5408R"><span id="translatedtitle">Fluctuating-bias controlled <span class="hlt">electron</span> <span class="hlt">transport</span> in molecular junctions</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ridley, Michael; MacKinnon, Angus; Kantorovich, Lev</p> <p>2016-05-01</p> <p>We consider the problem of <span class="hlt">transport</span> through a multiterminal molecular junction in the presence of a stochastic bias, which can also be used to describe <span class="hlt">transport</span> through fluctuating molecular energy levels. To describe these effects, we first make a simple extension of our previous work [Phys. Rev. B 91, 125433 (2015), 10.1103/PhysRevB.91.125433] to show that the problem of tunneling through noisy energy levels can be mapped onto the problem of a noisy driving bias, which appears in the Kadanoff-Baym equations for this system in an analogous manner to the driving term in the Langevin equation for a classical circuit. This formalism uses the nonequilibrium Green's function method to obtain analytically closed formulas for <span class="hlt">transport</span> quantities within the wide-band limit approximation for an arbitrary time-dependent bias and it is automatically partition free. We obtain exact closed formulas for both the colored and white noise-averaged current at all times. In the long-time limit, these formulas possess a Landauer-Büttiker-type structure which enables the extraction of an effective transmission coefficient for the <span class="hlt">transport</span>. Expanding the Fermi function into a series of simple poles, we find an exact formal relation between the parameters which characterize the bias fluctuations and the poles of the Fermi function. This enables us to describe the effect of the temperature and the strength of the fluctuations on the averaged current which we interpret as a quantum analog to the classical fluctuation-dissipation theorem. We use these results to convincingly refute some recent results on the multistability of the current through a fluctuating level, simultaneously verifying that our formalism satisfies some well-known theorems on the asymptotic current. Finally, we present numerical results for the current through a molecular chain which demonstrate a transition from nonlinear to linear I -V characteristics as the strength of fluctuations is increased, as well as a</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2004MPLB...18..847R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2004MPLB...18..847R"><span id="translatedtitle"><span class="hlt">Electronic</span> <span class="hlt">Transport</span> and Thermopower in Aperiodic DNA Sequences</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Roche, Stephan; Maciá, Enrique</p> <p></p> <p>A detailed study of charge <span class="hlt">transport</span> properties of synthetic and genomic DNA sequences is reported. Genomic sequences of the Chromosome 22, λ-bacteriophage, and D1s80 genes of Human and Pygmy chimpanzee are considered in this work, and compared with both periodic and quasiperiodic (Fibonacci) sequences of nucleotides. Charge transfer efficiency is compared for all these different sequences, and large variations in charge transfer efficiency, stemming from sequence-dependent effects, are reported. In addition, basic characteristics of tunneling currents, including contact effects, are described. Finally, the thermoelectric power of nucleobases connected in between metallic contacts at different temperatures is presented.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4756276','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4756276"><span id="translatedtitle">Distribution and dynamics of <span class="hlt">electron</span> <span class="hlt">transport</span> complexes in cyanobacterial thylakoid membranes☆</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Liu, Lu-Ning</p> <p>2016-01-01</p> <p>The cyanobacterial thylakoid membrane represents a system that can carry out both oxygenic photosynthesis and respiration simultaneously. The organization, interactions and mobility of components of these two <span class="hlt">electron</span> <span class="hlt">transport</span> pathways are indispensable to the biosynthesis of thylakoid membrane modules and the optimization of bioenergetic <span class="hlt">electron</span> flow in response to environmental changes. These are of fundamental importance to the metabolic robustness and plasticity of cyanobacteria. This review summarizes our current knowledge about the distribution and dynamics of <span class="hlt">electron</span> <span class="hlt">transport</span> components in cyanobacterial thylakoid membranes. Global understanding of the principles that govern the dynamic regulation of <span class="hlt">electron</span> <span class="hlt">transport</span> pathways in nature will provide a framework for the design and synthetic engineering of new bioenergetic machinery to improve photosynthesis and biofuel production. This article is part of a Special Issue entitled: Organization and dynamics of bioenergetic systems in bacteria, edited by Conrad Mullineaux. PMID:26619924</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2000SPIE.4348...39M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2000SPIE.4348...39M"><span id="translatedtitle">Spin-polarized <span class="hlt">electron</span> <span class="hlt">transport</span> and emission from strained superlattices</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Mamaev, Yuri A.; Subashiev, Arsen V.; Yashin, Yuri P.; Ambrajei, Anton N.; Roschansky, Alexander V.</p> <p>2000-02-01</p> <p>We report the results on polarized <span class="hlt">electron</span> emission from a new strained wide-gap AlxInyGa1-x-yAs/AlzGa1- zAs SL with tunable position of polarization maximum. These SL's were optimized to have a minimal conduction-band offset which comes from the band line-up between the semiconductor layers of the SL. The In layer content was chosen to give minimal conduction-band offset with large strain splitting of the V-band. Simultaneous changing of Al content in both SL layers provides variation of the structure band gap. We demonstrate that tuning of the SL to the excitation energy can be achieved without loss of the <span class="hlt">electron</span> polarization. The polarization of up to 84% was measured at room temperature.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2001SPIE.4348...39M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2001SPIE.4348...39M"><span id="translatedtitle">Spin-polarized <span class="hlt">electron</span> <span class="hlt">transport</span> and emission from strained superlattices</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Mamaev, Yuri A.; Subashiev, Arsen V.; Yashin, Yuri P.; Ambrajei, Anton N.; Roschansky, Alexander V.</p> <p>2001-02-01</p> <p>We report the results on polarized <span class="hlt">electron</span> emission from a new strained wide-gap AlxInyGa1-x-yAs/AlzGa1- zAs SL with tunable position of polarization maximum. These SL's were optimized to have a minimal conduction-band offset which comes from the band line-up between the semiconductor layers of the SL. The In layer content was chosen to give minimal conduction-band offset with large strain splitting of the V-band. Simultaneous changing of Al content in both SL layers provides variation of the structure band gap. We demonstrate that tuning of the SL to the excitation energy can be achieved without loss of the <span class="hlt">electron</span> polarization. The polarization of up to 84% was measured at room temperature.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2008JPhCS.100e2060A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2008JPhCS.100e2060A"><span id="translatedtitle"><span class="hlt">Electronic</span> <span class="hlt">transport</span> in double-strand DNA segments</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Albuquerque, E. L.; Mauriz, P. W.; Moreira, D. A.</p> <p>2008-03-01</p> <p>We report in this work a numerical study of the <span class="hlt">electronic</span> density of states in π-stacked arrays of DNA double-strand segments made up from the nucleotides guanine G, adenine A, cytosine C and thymine T. In order to reveal the relevance of the underlying correlations in the nucleotides distribution, we compare the results for a genomic DNA sequence, considering a segment of the first sequenced human chromosome 22 (Ch 22), with those of two artificial sequences forming a Rudin-Shapiro (RS) as well as a Fibonacci (FB) polyGC quasiperiodic sequences. Our theoretical method uses an <span class="hlt">electronic</span> tight-binding Hamiltonian suitable to describe the DNA segments modeled by the quasiperiodic chains.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/18487807','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/18487807"><span id="translatedtitle">Secure dissemination of <span class="hlt">electronic</span> healthcare records in distributed wireless <span class="hlt">environments</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Belsis, Petros; Vassis, Dimitris; Skourlas, Christos; Pantziou, Grammati</p> <p>2008-01-01</p> <p>A new networking paradigm has emerged with the appearance of wireless computing. Among else ad-hoc networks, mobile and ubiquitous <span class="hlt">environments</span> can boost the performance of systems in which they get applied. Among else, medical <span class="hlt">environments</span> are a convenient example of their applicability. With the utilisation of wireless infrastructures, medical data may be accessible to healthcare practitioners, enabling continuous access to medical data. Due to the critical nature of medical information, the design and implementation of these infrastructures demands special treatment in order to meet specific requirements; among else, special care should be taken in order to manage interoperability, security, and in order to deal with bandwidth and hardware resource constraints that characterize the wireless topology. In this paper we present an architecture that attempts to deal with these issues; moreover, in order to prove the validity of our approach we have also evaluated the performance of our platform through simulation in different operating scenarios.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017JEMat..46.2340P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017JEMat..46.2340P"><span id="translatedtitle"><span class="hlt">Electron</span> <span class="hlt">Transport</span> Parameters Study for Transition Metal-Doped Armchair Graphene Nanoribbon via Acoustical Phonon Interactions</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Pandya, Ankur; Jha, Prafulla K.</p> <p>2017-04-01</p> <p><span class="hlt">Electron</span> <span class="hlt">transport</span> parameters such as <span class="hlt">electron</span> effective mass, Fermi velocity of an <span class="hlt">electron</span> and <span class="hlt">electron</span> mobility are calculated for transition metal [manganese (Mn), cobalt (Co)]-doped armchair graphene nanoribbon (aGNR) via polar acoustical phonon [piezoelectric (PZ)] scattering and acoustical deformation potential (ADP) scattering under a high electric field and different doping concentrations. Moreover, the effect of dopant site on these <span class="hlt">electron</span> <span class="hlt">transport</span> parameters is also investigated. It is observed that the <span class="hlt">electron</span> effective mass is reduced significantly in doped aGNR in comparison to pure GNR. It is observed that the net <span class="hlt">electron</span> mobility contributed by both ADP and PZ mechanisms for Mn-doped aGNR as well as Co-doped aGNR varies in similar fashion as semiconductors wherein the net <span class="hlt">electron</span> mobility (ADP + PZ) for Mn-doped aGNR is greater than that for the Co-doped graphene nanoribbon. Moreover, it is found that there is no impact of variation in dopant site on the <span class="hlt">electron</span> <span class="hlt">transport</span> parameters considered in this study.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19950023032','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19950023032"><span id="translatedtitle">A hybrid <span class="hlt">electronically</span> scanned pressure module for cryogenic <span class="hlt">environments</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Chapman, J. J.; Hopson, P., Jr.; Kruse, N.</p> <p>1995-01-01</p> <p>Pressure is one of the most important parameters measured when testing models in wind tunnels. For models tested in the cryogenic <span class="hlt">environment</span> of the National Transonic Facility at NASA Langley Research Center, the technique of utilizing commercially available multichannel pressure modules inside the models is difficult due to the small internal volume of the models and the requirement of keeping the pressure transducer modules within an acceptable temperature range well above the -173 degrees C tunnel temperature. A prototype multichannel pressure transducer module has been designed and fabricated with stable, repeatable sensors and materials optimized for reliable performance in the cryogenic <span class="hlt">environment</span>. The module has 16 single crystal silicon piezoresistive pressure sensors electrostatically bonded to a metalized Pyrex substrate for sensing the wind tunnel model pressures. An integral temperature sensor mounted on each silicon micromachined pressure sensor senses real-time temperature fluctuations to within 0.1 degrees C to correct for thermally induced non-random sensor drift. The data presented here are from a prototype sensor module tested in the 0.3 M cryogenic tunnel and thermal equilibrium conditions in an environmental chamber which approximates the thermal <span class="hlt">environment</span> (-173 degrees C to +60 degrees C) of the National Transonic Facility.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/1170479','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/1170479"><span id="translatedtitle">Shewanella oneidensis MR-1 Nanowires are Outer Membrane and Periplasmic Extensions of the Extracellular <span class="hlt">Electron</span> <span class="hlt">Transport</span> Components</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Pirbadian, S.; Barchinger, S. E.; Leung, K. M.; Byun, H. S.; Jangir, Y.; Bouhenni, Rachida; Reed, Samantha B.; Romine, Margaret F.; Saffarini, Daad; Shi, Liang; Gorby, Yuri A.; Golbeck, J. H.; El-Naggar, Mohamed Y.</p> <p>2014-08-20</p> <p>Bacterial nanowires offer an extracellular <span class="hlt">electron</span> <span class="hlt">transport</span> (EET) pathway for linking the respiratory chain of bacteria to external surfaces, including oxidized metals in the <span class="hlt">environment</span> and engineered electrodes in renewable energy devices. Despite the global, environmental, and technological consequences of this biotic-abiotic interaction, the composition, physiological relevance, and <span class="hlt">electron</span> <span class="hlt">transport</span> mechanisms of bacterial nanowires remain unclear. We report the first in vivo observations of the formation and respiratory impact of nanowires in the model metal-reducing microbe Shewanella neidensis MR-1. Using live fluorescence measurements, immunolabeling, and quantitative gene expression analysis, we report that S. oneidensis MR-1 nanowires are extensions of the outer membrane and periplasm that include the multiheme cytochromes responsible for EET, rather than pilin-based structures, as previously thought. These bacterial nanowires were also associated with outer membrane vesicles and vesicle chains, structures ubiquitous in gram-negative bacteria. Redoxfunctionalized membrane and vesicular extensions may represent a general microbial strategy for <span class="hlt">electron</span> <span class="hlt">transport</span> and energy distribution.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li class="active"><span>22</span></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li><a href="#" onclick='return showDiv("page_24");'>24</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_22 --> <div id="page_23" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li class="active"><span>23</span></li> <li><a href="#" onclick='return showDiv("page_24");'>24</a></li> <li><a href="#" onclick='return showDiv("page_25");'>25</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="441"> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4156777','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4156777"><span id="translatedtitle">Shewanella oneidensis MR-1 nanowires are outer membrane and periplasmic extensions of the extracellular <span class="hlt">electron</span> <span class="hlt">transport</span> components</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Pirbadian, Sahand; Barchinger, Sarah E.; Leung, Kar Man; Byun, Hye Suk; Jangir, Yamini; Bouhenni, Rachida A.; Reed, Samantha B.; Romine, Margaret F.; Saffarini, Daad A.; Shi, Liang; Gorby, Yuri A.; Golbeck, John H.; El-Naggar, Mohamed Y.</p> <p>2014-01-01</p> <p>Bacterial nanowires offer an extracellular <span class="hlt">electron</span> <span class="hlt">transport</span> (EET) pathway for linking the respiratory chain of bacteria to external surfaces, including oxidized metals in the <span class="hlt">environment</span> and engineered electrodes in renewable energy devices. Despite the global, environmental, and technological consequences of this biotic–abiotic interaction, the composition, physiological relevance, and <span class="hlt">electron</span> <span class="hlt">transport</span> mechanisms of bacterial nanowires remain unclear. We report, to our knowledge, the first in vivo observations of the formation and respiratory impact of nanowires in the model metal-reducing microbe Shewanella oneidensis MR-1. Live fluorescence measurements, immunolabeling, and quantitative gene expression analysis point to S. oneidensis MR-1 nanowires as extensions of the outer membrane and periplasm that include the multiheme cytochromes responsible for EET, rather than pilin-based structures as previously thought. These membrane extensions are associated with outer membrane vesicles, structures ubiquitous in Gram-negative bacteria, and are consistent with bacterial nanowires that mediate long-range EET by the previously proposed multistep redox hopping mechanism. Redox-functionalized membrane and vesicular extensions may represent a general microbial strategy for <span class="hlt">electron</span> <span class="hlt">transport</span> and energy distribution. PMID:25143589</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/25143589','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/25143589"><span id="translatedtitle">Shewanella oneidensis MR-1 nanowires are outer membrane and periplasmic extensions of the extracellular <span class="hlt">electron</span> <span class="hlt">transport</span> components.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Pirbadian, Sahand; Barchinger, Sarah E; Leung, Kar Man; Byun, Hye Suk; Jangir, Yamini; Bouhenni, Rachida A; Reed, Samantha B; Romine, Margaret F; Saffarini, Daad A; Shi, Liang; Gorby, Yuri A; Golbeck, John H; El-Naggar, Mohamed Y</p> <p>2014-09-02</p> <p>Bacterial nanowires offer an extracellular <span class="hlt">electron</span> <span class="hlt">transport</span> (EET) pathway for linking the respiratory chain of bacteria to external surfaces, including oxidized metals in the <span class="hlt">environment</span> and engineered electrodes in renewable energy devices. Despite the global, environmental, and technological consequences of this biotic-abiotic interaction, the composition, physiological relevance, and <span class="hlt">electron</span> <span class="hlt">transport</span> mechanisms of bacterial nanowires remain unclear. We report, to our knowledge, the first in vivo observations of the formation and respiratory impact of nanowires in the model metal-reducing microbe Shewanella oneidensis MR-1. Live fluorescence measurements, immunolabeling, and quantitative gene expression analysis point to S. oneidensis MR-1 nanowires as extensions of the outer membrane and periplasm that include the multiheme cytochromes responsible for EET, rather than pilin-based structures as previously thought. These membrane extensions are associated with outer membrane vesicles, structures ubiquitous in Gram-negative bacteria, and are consistent with bacterial nanowires that mediate long-range EET by the previously proposed multistep redox hopping mechanism. Redox-functionalized membrane and vesicular extensions may represent a general microbial strategy for <span class="hlt">electron</span> <span class="hlt">transport</span> and energy distribution.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/1334524','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/1334524"><span id="translatedtitle">Self-assembly of pi-conjugated peptides in aqueous <span class="hlt">environments</span> leading to energy-<span class="hlt">transporting</span> bioelectronic nanostructures</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Tavor, John</p> <p>2016-12-06</p> <p>The realization of new supramolecular pi-conjugated organic structures inspired and driven by peptide-based self-assembly will offer a new approach to interface with the biotic <span class="hlt">environment</span> in a way that will help to meet many DOE-recognized grand challenges. Previously, we developed pi-conjugated peptides that undergo supramolecular self-assembly into one-dimensional (1-D) organic <span class="hlt">electronic</span> nanomaterials under benign aqueous conditions. The intermolecular interactions among the pi-conjugated organic segments within these nanomaterials lead to defined perturbations of their optoelectronic properties and yield nanoscale conduits that support energy <span class="hlt">transport</span> within individual nanostructures and throughout bulk macroscopic collections of nanomaterials. Our objectives for future research are to construct and study biomimetic <span class="hlt">electronic</span> materials for energy-related technology optimized for harsher non-biological <span class="hlt">environments</span> where peptide-driven self-assembly enhances pi-stacking within nanostructured biomaterials, as detailed in the following specific tasks: (1) synthesis and detailed optoelectronic characterization of new pi-<span class="hlt">electron</span> units to embed within homogeneous self assembling peptides, (2) molecular and data-driven modeling of the nanomaterial aggregates and their higher-order assemblies, and (3) development of new hierarchical assembly paradigms to organize multiple <span class="hlt">electronic</span> subunits within the nanomaterials leading to heterogeneous <span class="hlt">electronic</span> properties (i.e. gradients and localized electric fields). These intertwined research tasks will lead to the continued development and fundamental mechanistic understanding of a powerful bioinspired materials set capable of making connections between nanoscale <span class="hlt">electronic</span> materials and macroscopic bulk interfaces, be they those of a cell, a protein or a device.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/22486492','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/22486492"><span id="translatedtitle">Study of <span class="hlt">electron</span> <span class="hlt">transport</span> in a Hall thruster by axial–radial fully kinetic particle simulation</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Cho, Shinatora Kubota, Kenichi; Funaki, Ikkoh; Watanabe, Hiroki; Iihara, Shigeyasu; Fuchigami, Kenji; Uematsu, Kazuo</p> <p>2015-10-15</p> <p><span class="hlt">Electron</span> <span class="hlt">transport</span> across a magnetic field in a magnetic-layer-type Hall thruster was numerically investigated for the future predictive modeling of Hall thrusters. The discharge of a 1-kW-class magnetic-layer-type Hall thruster designed for high-specific-impulse operation was modeled using an r-z two-dimensional fully kinetic particle code with and without artificial <span class="hlt">electron</span>-diffusion models. The thruster performance results showed that both <span class="hlt">electron</span> <span class="hlt">transport</span> models captured the experimental result within discrepancies less than 20% in thrust and discharge current for all the simulated operation conditions. The <span class="hlt">electron</span> cross-field <span class="hlt">transport</span> mechanism of the so-called anomalous diffusion was self-consistently observed in the simulation without artificial diffusion models; the effective <span class="hlt">electron</span> mobility was two orders of magnitude higher than the value obtained using the classical diffusion theory. To account for the self-consistently observed anomalous <span class="hlt">transport</span>, the oscillation of plasma properties was speculated. It was suggested that the enhanced random-walk diffusion due to the velocity oscillation of low-frequency <span class="hlt">electron</span> flow could explain the observed anomalous diffusion within an order of magnitude. The dominant oscillation mode of the <span class="hlt">electron</span> flow velocity was found to be 20 kHz, which was coupled to electrostatic oscillation excited by global ionization instability.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19880052987&hterms=Neutralization&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D80%26Ntt%3DNeutralization','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19880052987&hterms=Neutralization&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D80%26Ntt%3DNeutralization"><span id="translatedtitle">Energy <span class="hlt">transport</span> by energetic <span class="hlt">electrons</span> released during solar flares. II - Current filamentation and plasma heating</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Winglee, R. M.; Dulk, G. A.; Pritchett, P. L.</p> <p>1988-01-01</p> <p>Two-dimensional electrostatic particle simulations are performed in order to investigate energy <span class="hlt">transport</span> associated with the propagation of energetic <span class="hlt">electrons</span> through a flaring flux tube. Results indicate that as the energetic <span class="hlt">electrons</span> flow outward, a return current of ambient plasma <span class="hlt">electrons</span> is drawn inward (to maintain quasi-neutrality) which can be spatially separate from the primary current carried by the energetic <span class="hlt">electrons</span>. Return current <span class="hlt">electrons</span> are shown to accumulate on either side of the acceleration region of the energetic <span class="hlt">electrons</span>, and depletions of ambient plasma <span class="hlt">electrons</span> develop in the return current regions. Plasma ions accelerate across the field lines to produce current closure or charge neutralization, achieving energies comparable to those of the energetic <span class="hlt">electrons</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/25105780','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/25105780"><span id="translatedtitle"><span class="hlt">Electronic</span> conduction properties of indium tin oxide: single-particle and many-body <span class="hlt">transport</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Lin, Juhn-Jong; Li, Zhi-Qing</p> <p>2014-08-27</p> <p>Indium tin oxide (Sn-doped In2O3-δ or ITO) is a very interesting and technologically important transparent conducting oxide. This class of material has been extensively investigated for decades, with research efforts mostly focusing on the application aspects. The fundamental issues of the <span class="hlt">electronic</span> conduction properties of ITO from room temperature down to liquid-helium temperatures have rarely been addressed thus far. Studies of the electrical-<span class="hlt">transport</span> properties over a wide range of temperature are essential to unravelling the underlying <span class="hlt">electronic</span> dynamics and microscopic <span class="hlt">electronic</span> parameters. In this topical review, we show that one can learn rich physics in ITO material, including the semi-classical Boltzmann <span class="hlt">transport</span>, the quantum-interference <span class="hlt">electron</span> <span class="hlt">transport</span>, as well as the many-body Coulomb <span class="hlt">electron-electron</span> interaction effects in the presence of disorder and inhomogeneity (granularity). To fully reveal the numerous avenues and unique opportunities that the ITO material has provided for fundamental condensed matter physics research, we demonstrate a variety of charge <span class="hlt">transport</span> properties in different forms of ITO structures, including homogeneous polycrystalline thin and thick films, homogeneous single-crystalline nanowires and inhomogeneous ultrathin films. In this manner, we not only address new physics phenomena that can arise in ITO but also illustrate the versatility of the stable ITO material forms for potential technological applications. We emphasize that, microscopically, the novel and rich <span class="hlt">electronic</span> conduction properties of ITO originate from the inherited robust free-<span class="hlt">electron</span>-like energy bandstructure and low-carrier concentration (as compared with that in typical metals) characteristics of this class of material. Furthermore, a low carrier concentration leads to slow <span class="hlt">electron</span>-phonon relaxation, which in turn causes the experimentally observed (i) a small residual resistance ratio, (ii) a linear <span class="hlt">electron</span> diffusion thermoelectric power in</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://eric.ed.gov/?q=history+AND+water+AND+earth&pg=2&id=ED439909','ERIC'); return false;" href="http://eric.ed.gov/?q=history+AND+water+AND+earth&pg=2&id=ED439909"><span id="translatedtitle">Going Places, Making Choices: <span class="hlt">Transportation</span> and the <span class="hlt">Environment</span>. Curriculum Designed for Grades 9-12.</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>National 4-H Council, Chevy Chase, MD.</p> <p></p> <p>This curriculum packet includes a teacher's introduction and five curriculum units that explore how <span class="hlt">transportation</span> needs affect the <span class="hlt">environment</span>, including the quality of air and water, habitat, and global climate. These materials encourage teens to apply wisdom, ingenuity, and sound science to the choices they make. Units are: (1)…</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/23322278','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/23322278"><span id="translatedtitle">Tuning the photodriven <span class="hlt">electron</span> <span class="hlt">transport</span> within the columnar perylenediimide stacks by changing the π-extent of the <span class="hlt">electron</span> donors.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Supur, Mustafa; Fukuzumi, Shunichi</p> <p>2013-02-21</p> <p>Photodriven <span class="hlt">electron-transport</span> properties of the self-assemblies of N,N'-di(2-(trimethylammoniumiodide)ethylene)perylenediimide stacks (TAIPDI)(n) with three <span class="hlt">electron</span> donors, disodium 4,4'-bis(2-sulfonatostyryl)biphenyl (BSSBP, stilbene-420), sodium 9,10-dimethoxyanthracene-2-sulfonate (DANS) and disodium 6-amino-1,3-naphthalenedisulfonate (ANADS) have been studied in water. These <span class="hlt">electron</span> donors vary in their π-extent to adjust the <span class="hlt">electronic</span> coupling and the distance with the PDI stacks. Possessing the largest π-extent, BSSBP has strong π-π interactions as well as ionic interactions with (TAIPDI)(n). Instead of π-stacking with TAIPDI planes, DANS and ANADS, with a relatively small π-extent, are embedded in the side chains of TAIPDIs via ionic interactions, resulting in a distance increment from the aromatic TAIPDI cores. After excitation, the BSSBP-(TAIPDI)(n) system exhibits fast charge separation (0.70 ps) and relatively slow charge recombination (485 ps) due to intermolecular <span class="hlt">electron</span> delocalization along the TAIPDI stacks. On the other hand, charge separation in DANS-(TAIPDI)(n) and ANADS-(TAIPDI)(n) occurs within 1.5 and 1.6 ns, respectively, calculated from the quenching of singlet excited states. The lifetimes of charge-separated states are determined to be 44 and 96 μs, at least 10(5) times slower than that of BSSBP-(TAIPDI)(n) due to remarkably improved <span class="hlt">electron</span> <span class="hlt">transport</span> throughout the (TAIPDI)(n).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012PhDT.......186G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012PhDT.......186G"><span id="translatedtitle">Breaking the barriers of all-polymer solar cells: Solving <span class="hlt">electron</span> <span class="hlt">transporter</span> and morphology problems</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Gavvalapalli, Nagarjuna</p> <p></p> <p>All-polymer solar cells (APSC) are a class of organic solar cells in which hole and <span class="hlt">electron</span> <span class="hlt">transporting</span> phases are made of conjugated polymers. Unlike polymer/fullerene solar cell, photoactive material of APSC can be designed to have hole and <span class="hlt">electron</span> <span class="hlt">transporting</span> polymers with complementary absorption range and proper frontier energy level offset. However, the highest reported PCE of APSC is 5 times less than that of polymer/fullerene solar cell. The low PCE of APSC is mainly due to: i) low charge separation efficiency; and ii) lack of optimal morphology to facilitate charge transfer and <span class="hlt">transport</span>; and iii) lack of control over the exciton and charge <span class="hlt">transport</span> in each phase. My research work is focused towards addressing these issues. The charge separation efficiency of APSC can be enhanced by designing novel <span class="hlt">electron</span> <span class="hlt">transporting</span> polymers with: i) broad absorption range; ii) high <span class="hlt">electron</span> mobility; and iii) high dielectric constant. In addition to with the above parameters chemical and <span class="hlt">electronic</span> structure of the repeating unit of conjugated polymer also plays a role in charge separation efficiency. So far only three classes of <span class="hlt">electron</span> <span class="hlt">transporting</span> polymers, CN substituted PPV, 2,1,3-benzothiadiazole derived polymers and rylene diimide derived polymers, are used in APSC. Thus to enhance the charge separation efficiency new classes of <span class="hlt">electron</span> <span class="hlt">transporting</span> polymers with the above characteristics need to be synthesized. I have developed a new straightforward synthetic strategy to rapidly generate new classes of <span class="hlt">electron</span> <span class="hlt">transporting</span> polymers with different chemical and <span class="hlt">electronic</span> structure, broad absorption range, and high <span class="hlt">electron</span> mobility from readily available <span class="hlt">electron</span> deficient monomers. In APSCs due to low entropy of mixing, polymers tend to micro-phase segregate rather than forming the more useful nano-phase segregation. Optimizing the polymer blend morphology to obtain nano-phase segregation is specific to the system under study, time consuming, and not</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=227117','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=227117"><span id="translatedtitle">The knowledge workstation: an <span class="hlt">electronic</span> <span class="hlt">environment</span> for knowledge management.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Lucier, R E; Matheson, N W; Butter, K A; Reynolds, R E</p> <p>1988-01-01</p> <p>This paper focuses on the creation of the IAIMS workstation in the context of the outcomes of a year-long IAIMS strategic planning process at the Johns Hopkins Medical Institutions (JHMI). These outcomes include a long-term institutional vision for a functional knowledge management <span class="hlt">environment</span>, a JHMI IAIMS model, a strategic plan, and two model prototypes. The functional requirements and specific implementation strategies for the IAIMS workstation, the prototype for managing the knowledge base of the published biomedical literature, are discussed in detail. PMID:3416102</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011AGUFM.H44C..03B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011AGUFM.H44C..03B"><span id="translatedtitle">Multi-dimensional Modeling of Fullerene (C60) Nanoparticle <span class="hlt">Transport</span> in the Subsurface <span class="hlt">Environment</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Bai, C.; Li, Y.</p> <p>2011-12-01</p> <p>The escalating production and consumption of engineered nanomaterials may lead to increased release into groundwater. A number of studies have revealed the potential human health effects and aquatic toxicity of nanomaterials. Understanding the fate and <span class="hlt">transport</span> of engineered nanomaterials is very important for evaluating their potential risks to human and ecological health. While a lot of efforts have been put forward in this area, limited work has been conducted to evaluate engineered nanomaterial <span class="hlt">transport</span> in multi-dimension and at field scale. In this work, we simulate the <span class="hlt">transport</span> of fullerene aggregates (nC60), a widely used engineered nanomaterial, in a multi-dimensional <span class="hlt">environment</span>. A Modular Three-Dimensional Multispecies <span class="hlt">Transport</span> Model (MT3DMS) was modified to incorporate the <span class="hlt">transport</span> and retention of nC60. The modified MT3DMS was validated by comparing with analytical solutions and one-dimensional numerical simulation results. The validated simulator was then used to simulate nC60 <span class="hlt">transport</span> in two- and three-dimensional field sites. Hypothetical scenarios for nanomaterial entering the subsurface <span class="hlt">environment</span>, including entering from an injection well and releasing from a waste site were investigated. Influences of injection rate, groundwater velocity, ground water recharge rate, subsurface heterogeneity, and nanomaterial size and surface property were evaluated. Insights gained from this work will be discussed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2008APS..DPPTP6019R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2008APS..DPPTP6019R"><span id="translatedtitle">Development of <span class="hlt">electron</span> thermal <span class="hlt">transport</span> model in DIII-D discharges</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Rafiq, T.; Pankin, A. Y.; Bateman, G.; Kritz, A. H.; Halpern, F. D.; Callen, J. D.</p> <p>2008-11-01</p> <p>The <span class="hlt">electron</span> thermal <span class="hlt">transport</span> in tokamak plasmas is investigated with predictive integrated modeling simulations using a choice of different <span class="hlt">electron</span> thermal <span class="hlt">transport</span> models. Two models for <span class="hlt">transport</span> driven by <span class="hlt">Electron</span> Temperature Gradient (ETG) modes are considered: (1) the ETG part of the GLF23 <span class="hlt">transport</span> model; and (2) the Horton model for the the electromagnetic part of the ETG anomalous <span class="hlt">transport</span> [1]. These models are combined with the paleoclassical model [2] for <span class="hlt">electron</span> thermal <span class="hlt">transport</span>. ASTRA predictive simulation results obtained using these models are compared with one another and compared with experimental data from DIII-D H-mode discharges in an effort to discriminate among the models. It is found that the electromagnetic limit of the Horton model is important near the magnetic axis where the ETG mode in the GLF23 model is below threshold. The paleoclassical model is found to be needed to produce the observed edge pedestal in the DIII-D simulations. [1] W. Horton, B. G. Hong, and W. M. Tang, Phys. Fluids 31, 2971 (1988). [2] J. D. Callen, Nucl. Fusion 45, 1120 (2005).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/22391741','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/22391741"><span id="translatedtitle"><span class="hlt">Electronic</span> <span class="hlt">transport</span> properties of one dimensional lithium nanowire using density functional theory</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Thakur, Anil; Kumar, Arun; Chandel, Surjeet; Ahluwalia, P. K.</p> <p>2015-05-15</p> <p>Single nanowire electrode devices are a unique platform for studying as energy storage devices. Lithium nanowire is of much importance in lithium ion batteries and therefore has received a great deal of attention in past few years. In this paper we investigated structural and <span class="hlt">electronic</span> <span class="hlt">transport</span> properties of Li nanowire using density functional theory (DFT) with SIESTA code. <span class="hlt">Electronic</span> <span class="hlt">transport</span> properties of Li nanowire are investigated theoretically. The calculations are performed in two steps: first an optimized geometry for Li nanowire is obtained using DFT calculations, and then the <span class="hlt">transport</span> relations are obtained using NEGF approach. SIESTA and TranSIESTA simulation codes are used in the calculations correspondingly. The electrodes are chosen to be the same as the central region where <span class="hlt">transport</span> is studied, eliminating current quantization effects due to contacts and focusing the <span class="hlt">electronic</span> <span class="hlt">transport</span> study to the intrinsic structure of the material. By varying chemical potential in the electrode regions, an I-V curve is traced which is in agreement with the predicted behavior. Agreement of bulk properties of Li with experimental values make the study of <span class="hlt">electronic</span> and <span class="hlt">transport</span> properties in lithium nanowires interesting because they are promising candidates as bridging pieces in nanoelectronics. Transmission coefficient and V-I characteristic of Li nano wire indicates that Li nanowire can be used as an electrode device.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AIPC.1661h0031T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AIPC.1661h0031T"><span id="translatedtitle"><span class="hlt">Electronic</span> <span class="hlt">transport</span> properties of one dimensional lithium nanowire using density functional theory</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Thakur, Anil; Kumar, Arun; Chandel, Surjeet; Ahluwalia, P. K.</p> <p>2015-05-01</p> <p>Single nanowire electrode devices are a unique platform for studying as energy storage devices. Lithium nanowire is of much importance in lithium ion batteries and therefore has received a great deal of attention in past few years. In this paper we investigated structural and <span class="hlt">electronic</span> <span class="hlt">transport</span> properties of Li nanowire using density functional theory (DFT) with SIESTA code. <span class="hlt">Electronic</span> <span class="hlt">transport</span> properties of Li nanowire are investigated theoretically. The calculations are performed in two steps: first an optimized geometry for Li nanowire is obtained using DFT calculations, and then the <span class="hlt">transport</span> relations are obtained using NEGF approach. SIESTA and TranSIESTA simulation codes are used in the calculations correspondingly. The electrodes are chosen to be the same as the central region where <span class="hlt">transport</span> is studied, eliminating current quantization effects due to contacts and focusing the <span class="hlt">electronic</span> <span class="hlt">transport</span> study to the intrinsic structure of the material. By varying chemical potential in the electrode regions, an I-V curve is traced which is in agreement with the predicted behavior. Agreement of bulk properties of Li with experimental values make the study of <span class="hlt">electronic</span> and <span class="hlt">transport</span> properties in lithium nanowires interesting because they are promising candidates as bridging pieces in nanoelectronics. Transmission coefficient and V-I characteristic of Li nano wire indicates that Li nanowire can be used as an electrode device.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017CP....485..125I','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017CP....485..125I"><span id="translatedtitle">State-specific <span class="hlt">transport</span> properties of partially ionized flows of <span class="hlt">electronically</span> excited atomic gases</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Istomin, V. A.; Kustova, E. V.</p> <p>2017-03-01</p> <p>State-to-state approach for theoretical study of <span class="hlt">transport</span> properties in atomic gases with excited <span class="hlt">electronic</span> degrees of freedom of both neutral and ionized species is developed. The dependence of atomic radius on the <span class="hlt">electronic</span> configuration of excited atoms is taken into account in the <span class="hlt">transport</span> algorithm. Different cutoff criteria for increasing atomic radius are discussed and the limits of applicability for these criteria are evaluated. The validity of a Slater-like model for the calculation of state-resolved <span class="hlt">transport</span> coefficients in neutral and ionized atomic gases is shown. For ionized flows, a method of evaluation for effective cross-sections of resonant charge-transfer collisions is suggested. Accurate kinetic theory algorithms for modelling the state-specific <span class="hlt">transport</span> properties are applied for the prediction of <span class="hlt">transport</span> coefficients in shock heated flows. Based on the numerical observations, different distributions over <span class="hlt">electronic</span> states behind the shock front are considered. For the Boltzmann-like distributions at temperatures greater than 14,000 K, an important effect of <span class="hlt">electronic</span> excitation on the partial thermal conductivity and viscosity coefficients is found for both neutral and ionized atomic gases: increasing radius of excited atoms causes a strong decrease in these <span class="hlt">transport</span> coefficients. Similarly, the presence of <span class="hlt">electronically</span> excited states with increased atomic radii leads to reduced diffusion coefficients. Nevertheless the overall impact of increasing effective cross-sections on the <span class="hlt">transport</span> properties just behind the shock front under hypersonic reentry conditions is found to be minor since the populations of high-lying <span class="hlt">electronic</span> energy levels behind the shock waves are low.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016APS..MARC19006R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016APS..MARC19006R"><span id="translatedtitle"><span class="hlt">Transport</span> and Raman signatures of <span class="hlt">electron</span>-doped SmNiO3 thin films</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ramadoss, Koushik; Mandal, Nirajan; Zhou, You; Chen, Yong; Ramanathan, Shriram</p> <p></p> <p>We report low temperature <span class="hlt">transport</span> and Raman spectroscopy measurements of <span class="hlt">electron</span>-doped SmNiO3 (SNO) thin films. It has been shown that pristine SNO films can be doped with <span class="hlt">electrons</span> using hydrogen. Our <span class="hlt">transport</span> measurements indicate a Coulomb interaction dominated variable range hopping (VRH) for <span class="hlt">electron</span>-doped samples whereas the pristine films show a Mott type VRH mechanism at low temperatures. The <span class="hlt">electron</span>-doped samples display a strong localization which can be correlated with the high spin state of Ni2+ ions. The spatial Raman map shows a remarkable shift of about 167 cm-1 with <span class="hlt">electron</span> doping thus serving as a spectroscopic tool to investigate hydrogen in our films. Birck Nanotechnology Center, Purdue University.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/25050525','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/25050525"><span id="translatedtitle">Centimeter-long <span class="hlt">electron</span> <span class="hlt">transport</span> in marine sediments via conductive minerals.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Malvankar, Nikhil S; King, Gary M; Lovley, Derek R</p> <p>2015-02-01</p> <p>Centimeter-long <span class="hlt">electron</span> conduction through marine sediments, in which <span class="hlt">electrons</span> derived from sulfide in anoxic sediments are <span class="hlt">transported</span> to oxygen in surficial sediments, may have an important influence on sediment geochemistry. Filamentous bacteria have been proposed to mediate the <span class="hlt">electron</span> <span class="hlt">transport</span>, but the filament conductivity could not be verified and other mechanisms are possible. Surprisingly, previous investigations have never actually measured the sediment conductivity or its basic physical properties. Here we report direct measurements that demonstrate centimeter-long <span class="hlt">electron</span> flow through marine sediments, with conductivities sufficient to account for previously estimated <span class="hlt">electron</span> fluxes. Conductivity was lost for oxidized sediments, which contrasts with the previously described increase in the conductivity of microbial biofilms upon oxidation. Adding pyrite to the sediments significantly enhanced the conductivity. These results suggest that the role of conductive minerals, which are more commonly found in sediments than centimeter-long microbial filaments, need to be considered when modeling marine sediment biogeochemistry.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/22412929','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/22412929"><span id="translatedtitle">Theoretical study of <span class="hlt">electronic</span> <span class="hlt">transport</span> properties of a graphene-silicene bilayer</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Berdiyorov, G. R.; Bahlouli, H.; Peeters, F. M.</p> <p>2015-06-14</p> <p><span class="hlt">Electronic</span> <span class="hlt">transport</span> properties of a graphene-silicene bilayer system are studied using density-functional theory in combination with the nonequilibrium Green's function formalism. Depending on the energy of the <span class="hlt">electrons</span>, the transmission can be larger in this system as compared to the sum of the transmissions of separated graphene and silicene monolayers. This effect is related to the increased <span class="hlt">electron</span> density of states in the bilayer sample. At some energies, the <span class="hlt">electronic</span> states become localized in one of the layers, resulting in the suppression of the <span class="hlt">electron</span> transmission. The effect of an applied voltage on the transmission becomes more pronounced in the layered sample as compared to graphene due to the larger variation of the electrostatic potential profile. Our findings will be useful when creating hybrid nanoscale devices where enhanced <span class="hlt">transport</span> properties will be desirable.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4885465','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4885465"><span id="translatedtitle">Built <span class="hlt">Environment</span> and Active <span class="hlt">Transport</span> to School (BEATS) Study: protocol for a cross-sectional study</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Mandic, Sandra; Williams, John; Moore, Antoni; Hopkins, Debbie; Flaherty, Charlotte; Wilson, Gordon; García Bengoechea, Enrique; Spence, John C</p> <p>2016-01-01</p> <p>Introduction Active <span class="hlt">transport</span> to school (ATS) is a convenient way to increase physical activity and undertake an environmentally sustainable travel practice. The Built <span class="hlt">Environment</span> and Active <span class="hlt">Transport</span> to School (BEATS) Study examines ATS in adolescents in Dunedin, New Zealand, using ecological models for active <span class="hlt">transport</span> that account for individual, social, environmental and policy factors. The study objectives are to: (1) understand the reasons behind adolescents and their parents' choice of <span class="hlt">transport</span> mode to school; (2) examine the interaction between the <span class="hlt">transport</span> choices, built <span class="hlt">environment</span>, physical activity and weight status in adolescents; and (3) identify policies that promote or hinder ATS in adolescents. Methods and analysis The study will use a mixed-method approach incorporating both quantitative (surveys, anthropometry, accelerometers, Geographic Information System (GIS) analysis, mapping) and qualitative methods (focus groups, interviews) to gather data from students, parents, teachers and school principals. The core data will include accelerometer-measured physical activity, anthropometry, GIS measures of the built <span class="hlt">environment</span> and the use of maps indicating route to school (students)/work (parents) and perceived safe/unsafe areas along the route. To provide comprehensive data for understanding how to change the infrastructure to support ATS, the study will also examine complementary variables such as individual, family and social factors, including student and parental perceptions of walking and cycling to school, parental perceptions of different modes of <span class="hlt">transport</span> to school, perceptions of the neighbourhood <span class="hlt">environment</span>, route to school (students)/work (parents), perceptions of driving, use of information communication technology, reasons for choosing a particular school and student and parental physical activity habits, screen time and weight status. The study has achieved a 100% school recruitment rate (12 secondary schools). Ethics and</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011PhDT.......183C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011PhDT.......183C"><span id="translatedtitle"><span class="hlt">Electronic</span> and Ionic <span class="hlt">Transport</span> in Carbon Nanotubes and Other Nanostructures</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Cao, Di</p> <p></p> <p>This thesis describes several experiments based on carbon nanotube nanofludic devices and field-effect transistors. The first experiment detected ion and molecule translocation through one single-walled carbon nanotube (SWCNT) that spans a barrier between two fluid reservoirs. The electrical ionic current is measured. Translocation of small single stranded DNA oligomers is marked by large transient increases in current through the tube and confirmed by a PCR (polymerase chain reaction) analysis. Carbon nanotubes simplify the construction of nanopores, permit new types of electrical measurement, and open new avenues for control of DNA translocation. The second experiment constructed devices in which the interior of a single-walled carbon nanotube field-effect transistor (CNT-FET) acts as a nanofluidic channel that connects two fluid reservoirs, permitting measurement of the <span class="hlt">electronic</span> properties of the SWCNT as it is wetted by an analyte. Wetting of the inside of the SWCNT by water turns the transistor on, while wetting of the outside has little effect. This finding may provide a new method to investigate water behavior at nanoscale. This also opens a new avenue for building sensors in which the SWCNT functions as an <span class="hlt">electronic</span> detector. This thesis also presents some experiments that related to nanofabrication, such as construction of FET with tin sulfide (SnS) quantum ribbon. This work demonstrates the application of solution processed IV-VI semiconductor nanostructures in nanoscale devices.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li class="active"><span>23</span></li> <li><a href="#" onclick='return showDiv("page_24");'>24</a></li> <li><a href="#" onclick='return showDiv("page_25");'>25</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_23 --> <div id="page_24" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li class="active"><span>24</span></li> <li><a href="#" onclick='return showDiv("page_25");'>25</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="461"> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/6601907','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/6601907"><span id="translatedtitle">Hollow-fiber membranes for photosensitized <span class="hlt">electron</span> <span class="hlt">transport</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Wamser, C.C.; Otvos, J.W.; Calvin, M.</p> <p>1981-01-01</p> <p>Commercially available cellulose acetate hollow fiber membranes have been investigated for possible use in artificial photosynthesis solar energy schemes. The function of the membrane is to contain the photosensitizer and to separate the oxidized and reduced species which result from photosensitized <span class="hlt">electron</span> transfer reactions on each side of the membrane wall. Membranes were successfully modified by a process of soaking in a THF solution saturated with porphyrin, followed by a water rinse. This procedure gives dark purple fibers which contain up to 30 mM zinc tetraphenylporphyrin in the fiber walls. A plumbing system has been developed to allow flow of a solution through the inner channels of a 24-fiber bundle while it is immersed in a separate outer solution. Preliminary studies indicate that the fibers are somewhat permeable to both EDTA and dimethyl viologen, the <span class="hlt">electron</span> donor and acceptor molecules, respectively. Preliminary photochemical studies on cut-up pieces of the treated fiber indicate that it does photosensitize a reaction between EDTA and dimethyl viologen in aqueous solution.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012APS..MAR.S1260R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012APS..MAR.S1260R"><span id="translatedtitle">Dependence of magnetic field and <span class="hlt">electronic</span> <span class="hlt">transport</span> of Mn4 Single-molecule magnet in a Single-<span class="hlt">Electron</span> Transistor</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Rodriguez, Alvar; Singh, Simranjeet; Haque, Firoze; Del Barco, Enrique; Nguyen, Tu; Christou, George</p> <p>2012-02-01</p> <p>Dependence of magnetic field and <span class="hlt">electronic</span> <span class="hlt">transport</span> of Mn4 Single-molecule magnet in a Single-<span class="hlt">Electron</span> Transistor A. Rodriguez, S. Singh, F. Haque and E. del Barco Department of Physics, University of Central Florida, 4000 Central Florida Blvd., Orlando, Florida 32816 USA T. Nguyen and G. Christou Department of Chemistry, University of Florida, Gainesville, Florida 32611 USA Abstract We have performed single-<span class="hlt">electron</span> <span class="hlt">transport</span> measurements on a series of Mn-based low-nuclearity single-molecule magnets (SMM) observing Coulomb blockade. SMMs with well isolated and low ground spin states, i.e. S = 9/2 (Mn4) and S = 6 (Mn3) were chosen for these studies, such that the ground spin multiplet does not mix with levels of other excited spin states for the magnetic fields (H = 0-8 T) employed in the experiments. Different functionalization groups were employed to change the mechanical, geometrical and <span class="hlt">transport</span> characteristics of the molecules when deposited from liquid solution on the transistors. Electromigration-broken three-terminal single-<span class="hlt">electron</span> transistors were used. Results obtained at temperatures down to 240 mK and in the presence of high magnetic fields will be shown.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/24016422','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/24016422"><span id="translatedtitle">Effect of heat stress and feeding phosphorus levels on pig <span class="hlt">electron</span> <span class="hlt">transport</span> chain gene expression.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Weller, M M D C A; Alebrante, L; Campos, P H R F; Saraiva, A; Silva, B A N; Donzele, J L; Oliveira, R F M; Silva, F F; Gasparino, E; Lopes, P S; Guimarães, S E F</p> <p>2013-12-01</p> <p>The purpose of this study was to evaluate the effect of temperature and different levels of available phosphorus (aP) on the expression of nine genes encoding <span class="hlt">electron</span> <span class="hlt">transport</span> chain proteins in the Longissimus dorsi (LD) muscle of pigs. Two trials were carried out using 48 high-lean growth pigs from two different growth phases: from 15 to 30 kg (phase 1) and from 30 to 60 kg (phase 2). Pigs from growth phase 1 were fed with three different levels of dietary aP (0.107%, 0.321% or 0.535%) and submitted either to a thermoneutral (24°C and RH at 76%) or to a heat stress (34°C and RH at 70%) <span class="hlt">environment</span>. Pigs from growth phase 2 were fed with three different levels of dietary aP (0.116%, 0.306% or 0.496%) and submitted either to a thermoneutral (22ºC and RH at 77%) or to a heat stress (32ºC and RH at 73%) <span class="hlt">environment</span>. Heat stress decreased (P<0.001) average daily feed intake at both growth phases. At 24°C, pigs in phase 1 fed the 0.321% aP diet had greater average daily gain and feed conversion (P<0.05) than those fed the 0.107% or 0.535% while, at 34°C pigs fed the 0.535% aP had the best performance (P<0.05). Pigs from phase 2 fed the 0.306% aP had best performance in both thermal <span class="hlt">environments</span>. Gene expression profile was analyzed by quantitative real-time polymerase chain reaction. Irrespective of growing phase, the expression of six genes was lower (P<0.05) at high temperature than at thermoneutrality. The lower expression of these genes under high temperatures evidences the effects of heat stress by decreasing oxidative metabolism, through adaptive physiological mechanisms in order to reduce heat production. In pigs from phase 1, six genes were differentially expressed across aP levels (P<0.05) in the thermoneutral and one gene in the heat stress. In pigs from phase 2, two genes were differentially expressed across aP levels (P<0.05) in both thermal <span class="hlt">environments</span>. These data revealed strong evidence that phosphorus and thermal <span class="hlt">environments</span> are key factors to</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1999PhDT.......173C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1999PhDT.......173C"><span id="translatedtitle"><span class="hlt">Electron</span> <span class="hlt">transport</span> in the nanostructured titanium dioxide electrodes in the application of solar cells</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Cao, Fei</p> <p></p> <p>The high efficiency of dye sensitized nanostructured TiO 2 photoelectrochemical solar cells underlines the high charge transfer efficiency at the semiconductor/dye interface and the ability of the nanometer sized TiO2 particle network in intimate contact with the electrolyte to <span class="hlt">transport</span> the injected <span class="hlt">electrons</span> without significant losses. The operating mechanisms of these photoelectrochemical systems are reviewed. The focus of this dissertation is the photoelectrical properties of nanostructured TiO 2 films and the associated charge <span class="hlt">transport</span> process. Transient techniques, both in the time domain and frequency domain were used to probe the <span class="hlt">electron</span> <span class="hlt">transport</span> in the TiO2 electrodes. The conductivity of nanostructured TiO2 thin films increases several orders of magnitude under illumination yet the conductivity is very low in the dark, illustrating the fact that the conductivity is strongly dependent on the trapped charges in these films. Due to the lack of a strong electrical field, charge <span class="hlt">transport</span> only becomes efficient after the build up of a concentration gradient to drive the <span class="hlt">electron</span> <span class="hlt">transport</span> process, resulting in slow photocurrent and photovoltage transients in the photoelectrochemical cells. The open circuit photovoltages follow the conventional diode equation. This can be understood in terms of the Fermi level at the TiO2/tin oxide contact. The injection of <span class="hlt">electrons</span> leads to the increase of the Fermi level at the contact. The time constants obtained follow a simple power law relationship with the light intensity reflecting the kinetics of <span class="hlt">electron</span> <span class="hlt">transport</span> in the nanostructured electrodes. The essential features of the nonsteady state response can be described by a diffusion model where the <span class="hlt">electron</span> diffusion coefficient is dependent on light intensity. The lack of <span class="hlt">electron</span> migration can be rationalized by the fact that any electrical field in the porous electrodes may be neutralized by the mobile ions in the electrolyte.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/22264075','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/22264075"><span id="translatedtitle">Quantum <span class="hlt">transport</span> through disordered 1D wires: Conductance via localized and delocalized <span class="hlt">electrons</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Gopar, Víctor A.</p> <p>2014-01-14</p> <p>Coherent <span class="hlt">electronic</span> <span class="hlt">transport</span> through disordered systems, like quantum wires, is a topic of fundamental and practical interest. In particular, the exponential localization of <span class="hlt">electron</span> wave functions-Anderson localization-due to the presence of disorder has been widely studied. In fact, Anderson localization, is not an phenomenon exclusive to <span class="hlt">electrons</span> but it has been observed in microwave and acoustic experiments, photonic materials, cold atoms, etc. Nowadays, many properties of <span class="hlt">electronic</span> <span class="hlt">transport</span> of quantum wires have been successfully described within a scaling approach to Anderson localization. On the other hand, anomalous localization or delocalization is, in relation to the Anderson problem, a less studied phenomenon. Although one can find signatures of anomalous localization in very different systems in nature. In the problem of <span class="hlt">electronic</span> <span class="hlt">transport</span>, a source of delocalization may come from symmetries present in the system and particular disorder configurations, like the so-called Lévy-type disorder. We have developed a theoretical model to describe the statistical properties of <span class="hlt">transport</span> when <span class="hlt">electron</span> wave functions are delocalized. In particular, we show that only two physical parameters determine the complete conductance distribution.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015PhyA..435...15D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015PhyA..435...15D"><span id="translatedtitle"><span class="hlt">Electronic</span> <span class="hlt">transport</span> in disordered chains with saturable nonlinearity</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>dos Santos, J. L. L.; Nguyen, Ba Phi; de Moura, F. A. B. F.</p> <p>2015-10-01</p> <p>In this work we study numerically the dynamics of an initially localized wave packet in one-dimensional disordered chains with saturable nonlinearity. By using the generalized discrete nonlinear Schrödinger equation, we calculate two different physical quantities as a function of time, which are the participation number and the mean square displacement from the excitation site. From detailed numerical analysis, we find that the saturable nonlinearity can promote a sub-diffusive spreading of the wave packet even in the presence of diagonal disorder for a long time. In addition, we also investigate the effect of the saturated nonlinearity for initial times of the <span class="hlt">electronic</span> evolution thus showing the possibility of mobile breather-like modes.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/19278211','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/19278211"><span id="translatedtitle"><span class="hlt">Electronic</span> <span class="hlt">transport</span> on the nanoscale: ballistic transmission and Ohm's law.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Homoth, J; Wenderoth, M; Druga, T; Winking, L; Ulbrich, R G; Bobisch, C A; Weyers, B; Bannani, A; Zubkov, E; Bernhart, A M; Kaspers, M R; Möller, R</p> <p>2009-04-01</p> <p>If a current of <span class="hlt">electrons</span> flows through a normal conductor (in contrast to a superconductor), it is impeded by local scattering at defects as well as phonon scattering. Both effects contribute to the voltage drop observed for a macroscopic complex system as described by Ohm's law. Although this concept is well established, it has not yet been measured around individual defects on the atomic scale. We have measured the voltage drop at a monatomic step in real space by restricting the current to a surface layer. For the Si(111)-( [see text]3 x [see text]3)-Ag surface a monotonous transition with a width below 1 nm was found. A numerical analysis of the data maps the current flow through the complex network and the interplay between defect-free terraces and monatomic steps.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/22212732','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/22212732"><span id="translatedtitle">Monte Carlo <span class="hlt">electron</span>-photon <span class="hlt">transport</span> using GPUs as an accelerator: Results for a water-aluminum-water phantom</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Su, L.; Du, X.; Liu, T.; Xu, X. G.</p> <p>2013-07-01</p> <p>An <span class="hlt">electron</span>-photon coupled Monte Carlo code ARCHER - Accelerated Radiation-<span class="hlt">transport</span> Computations in Heterogeneous <span class="hlt">Environments</span> - is being developed at Rensselaer Polytechnic Institute as a software test bed for emerging heterogeneous high performance computers that utilize accelerators such as GPUs. In this paper, the preliminary results of code development and testing are presented. The <span class="hlt">electron</span> <span class="hlt">transport</span> in media was modeled using the class-II condensed history method. The <span class="hlt">electron</span> energy considered ranges from a few hundred keV to 30 MeV. Moller scattering and bremsstrahlung processes above a preset energy were explicitly modeled. Energy loss below that threshold was accounted for using the Continuously Slowing Down Approximation (CSDA). Photon <span class="hlt">transport</span> was dealt with using the delta tracking method. Photoelectric effect, Compton scattering and pair production were modeled. Voxelised geometry was supported. A serial ARHCHER-CPU was first written in C++. The code was then ported to the GPU platform using CUDA C. The hardware involved a desktop PC with an Intel Xeon X5660 CPU and six NVIDIA Tesla M2090 GPUs. ARHCHER was tested for a case of 20 MeV <span class="hlt">electron</span> beam incident perpendicularly on a water-aluminum-water phantom. The depth and lateral dose profiles were found to agree with results obtained from well tested MC codes. Using six GPU cards, 6x10{sup 6} histories of <span class="hlt">electrons</span> were simulated within 2 seconds. In comparison, the same case running the EGSnrc and MCNPX codes required 1645 seconds and 9213 seconds, respectively, on a CPU with a single core used. (authors)</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/21199273','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/21199273"><span id="translatedtitle">Transmission <span class="hlt">electron</span> microscopy and electrical <span class="hlt">transport</span> investigations performed on the same single-walled carbon nanotube</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Philipp, G.; Burghard, M.; Roth, S.</p> <p>1998-08-11</p> <p>Electrical <span class="hlt">transport</span> measurements and high resolution transmission <span class="hlt">electron</span> microscopy performed on the same (rope of) single-walled carbon nanotube(s) (SWCNTs) allow to establish links between structural and <span class="hlt">electronic</span> properties of the tubes. The tubes are deposited on <span class="hlt">electron</span> transparent ultrathin Si{sub 3}N{sub 4}-membranes bearing Cr/AuPd-electrodes defined by <span class="hlt">electron</span> beam lithography. TEM-micrographs of the setup reveal mostly ropes consisting of 2-3 tubes which also appear on a scanning force microscope image of the same area. A current-voltage trace of the ropes at 4.2 K is also presented.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2003EL.....61..674H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2003EL.....61..674H"><span id="translatedtitle"><span class="hlt">Transport</span> signatures of correlated disorder in a two-dimensional <span class="hlt">electron</span> gas</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Heinzel, T.; Jäggi, R.; Ribeiro, E.; Waldkirch, M. v.; Ensslin, K.; Ulloa, S. E.; Medeiros-Ribeiro, G.; Petroff, P. M.</p> <p>2003-03-01</p> <p>We report <span class="hlt">electronic</span> <span class="hlt">transport</span> measurements on two-dimensional <span class="hlt">electron</span> gases in a Ga[Al]As heterostructure with an embedded layer of InAs self-assembled quantum dots. At high InAs dot densities, pronounced Altshuler-Aronov-Spivak magnetoresistance oscillations are observed, which indicate short-range ordering of the potential landscape formed by the charged dots and the strain fields. The presence of these oscillations coincides with the observation of a metal-insulator transition, and a maximum in the <span class="hlt">electron</span> mobility as a function of the <span class="hlt">electron</span> density. Within a model based on correlated disorder, we establish a relation between these effects.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/22408372','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/22408372"><span id="translatedtitle">Influence of oblique magnetic field on <span class="hlt">electron</span> cross-field <span class="hlt">transport</span> in a Hall effect thruster</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Miedzik, Jan; Daniłko, Dariusz; Barral, Serge</p> <p>2015-04-15</p> <p>The effects of the inclination of the magnetic field with respect to the channel walls in a Hall effect thruster are numerically studied with the use of a one-dimensional quasi-neutral Particle-In-Cell model with guiding center approximation of <span class="hlt">electron</span> motion along magnetic lines. Parametric studies suggest that the incidence angle strongly influences <span class="hlt">electron</span> <span class="hlt">transport</span> across the magnetic field. In ion-focusing magnetic topologies, <span class="hlt">electrons</span> collide predominantly on the side of the magnetic flux tube closer to the anode, thus increasing the <span class="hlt">electron</span> cross-field drift. The opposite effect is observed in ion-defocussing topology.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012EML.....8..429M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012EML.....8..429M"><span id="translatedtitle">Preparation and characterization of oxadiazole based <span class="hlt">electron</span> <span class="hlt">transporting</span> thin films</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Mahajan, Aman; Aulakh, Ramanpreet Kaur; Bedi, R. K.</p> <p>2012-08-01</p> <p>To study the effect of aggregation of the 2-(4-biphenylyl)-5-phenyl-1,3,4-oxadiazole (PBD) molecule in solid state, thin films of PBD have been prepared by the thermal evaporation technique onto glass and quartz substrates under different experimental conditions. These films have been studied for their structural, optical and electrical properties. AFM investigations of the films revealed that the films were smooth, dense and crack free with RMS roughness of 11-14 nm. XRD measurements indicate that films deposited on quartz are more crystalline than films deposited on glass substrate. Both absorption and reflectance spectra over the wavelength range 200-800 nm have been recorded to find optical parameters, namely, absorption, extinction coefficient, refractive index and dielectric constants. The inter-band transition energies are found to lie within the range 3.45-3.49 eV. Optical studies of the films indicate that PBD molecules preferred J-aggregation. A prominent single emission peak in the range of 370-390 nm has been observed which confirms that the fluorescent property of this molecule is not quenched in the thin film state. The electrical conductivity results for the evaporated films exhibited semiconductor behaviour within the investigated field and temperature range. The nature of the substrate is found to be a useful tool to modify the film morphology and for enhancing the charge <span class="hlt">transport</span> within the films.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016ChPhB..25k7303Z','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016ChPhB..25k7303Z"><span id="translatedtitle"><span class="hlt">Electronic</span> <span class="hlt">transport</span> of bilayer graphene with asymmetry line defects</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Zhao, Xiao-Ming; Wu, Ya-Jie; Chen, Chan; Liang, Ying; Kou, Su-Peng</p> <p>2016-11-01</p> <p>In this paper, we study the quantum properties of a bilayer graphene with (asymmetry) line defects. The localized states are found around the line defects. Thus, the line defects on one certain layer of the bilayer graphene can lead to an electric <span class="hlt">transport</span> channel. By adding a bias potential along the direction of the line defects, we calculate the electric conductivity of bilayer graphene with line defects using the Landauer-Büttiker theory, and show that the channel affects the electric conductivity remarkably by comparing the results with those in a perfect bilayer graphene. This one-dimensional line electric channel has the potential to be applied in nanotechnology engineering. Project supported by the National Basic Research Program of China (Grant Nos. 2011CB921803 and 2012CB921704), the National Natural Science Foundation of China (Grant Nos. 11174035, 11474025, 11504285, and 11404090), the Specialized Research Fund for the Doctoral Program of Higher Education, China, the Fundamental Research Funds for the Central Universities, China, the Scientific Research Program Fund of the Shaanxi Provincial Education Department, China (Grant No. 15JK1363), and the Young Talent Fund of University Association for Science and Technology in Shaanxi Province, China.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/24601637','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/24601637"><span id="translatedtitle">Water promoting <span class="hlt">electron</span> hole <span class="hlt">transport</span> between tyrosine and cysteine in proteins via a special mechanism: double proton coupled <span class="hlt">electron</span> transfer.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Chen, Xiaohua; Ma, Guangcai; Sun, Weichao; Dai, Hongjing; Xiao, Dong; Zhang, Yanfang; Qin, Xin; Liu, Yongjun; Bu, Yuxiang</p> <p>2014-03-26</p> <p>The proton/<span class="hlt">electron</span> transfer reactions between cysteine residue (Cys) and tyrosinyl radical (Tyr(•)) are an important step for many enzyme-catalyzed processes. On the basis of the statistical analysis of protein data bank, we designed three representative models to explore the possible proton/<span class="hlt">electron</span> transfer mechanisms from Cys to Tyr(•) in proteins. Our ab initio calculations on simplified models and quantum mechanical/molecular mechanical (QM/MM) calculations on real protein <span class="hlt">environment</span> reveal that the direct <span class="hlt">electron</span> transfer between Cys and Tyr(•) is difficult to occur, but an inserted water molecule can greatly promote the proton/<span class="hlt">electron</span> transfer reactions by a double-proton-coupled <span class="hlt">electron</span> transfer (dPCET) mechanism. The inserted H2O plays two assistant roles in these reactions. The first one is to bridge the side chains of Tyr(•) and Cys via two hydrogen bonds, which act as the proton pathway, and the other one is to enhance the <span class="hlt">electron</span> overlap between the lone-pair orbital of sulfur atom and the π-orbital of phenol moiety and to function as <span class="hlt">electron</span> transfer pathway. This water-mediated dPCET mechanism may offer great help to understand the detailed <span class="hlt">electron</span> transfer processes between Tyr and Cys residues in proteins, such as the <span class="hlt">electron</span> transfer from Cys439 to Tyr730(•) in the class I ribonucleotide reductase.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://files.eric.ed.gov/fulltext/ED562393.pdf','ERIC'); return false;" href="http://files.eric.ed.gov/fulltext/ED562393.pdf"><span id="translatedtitle">What Do Context Aware <span class="hlt">Electronic</span> Alerts from Virtual Learning <span class="hlt">Environments</span> Tell Us about User Time & Location?</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Crane, Laura; Benachour, Phillip</p> <p>2013-01-01</p> <p>The paper describes the analysis of user location and time stamp information automatically logged when students receive and interact with <span class="hlt">electronic</span> updates from the University's virtual learning <span class="hlt">environment</span>. The <span class="hlt">electronic</span> updates are sent to students' mobile devices using RSS feeds. The mobile reception of such information can be received in…</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4934278','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4934278"><span id="translatedtitle">Quality Detection of Litchi Stored in Different <span class="hlt">Environments</span> Using an <span class="hlt">Electronic</span> Nose</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Xu, Sai; Lü, Enli; Lu, Huazhong; Zhou, Zhiyan; Wang, Yu; Yang, Jing; Wang, Yajuan</p> <p>2016-01-01</p> <p>The purpose of this paper was to explore the utility of an <span class="hlt">electronic</span> nose to detect the quality of litchi fruit stored in different <span class="hlt">environments</span>. In this study, a PEN3 <span class="hlt">electronic</span> nose was adopted to test the storage time and hardness of litchi that were stored in three different types of <span class="hlt">environment</span> (room temperature, refrigerator and controlled-atmosphere). After acquiring data about the hardness of the sample and from the <span class="hlt">electronic</span> nose, linear discriminant analysis (LDA), canonical correlation analysis (CCA), BP neural network (BPNN) and BP neural network-partial least squares regression (BPNN-PLSR), were employed for data processing. The experimental results showed that the hardness of litchi fruits stored in all three <span class="hlt">environments</span> decreased during storage. The litchi stored at room temperature had the fastest rate of decrease in hardness, followed by those stored in a refrigerator <span class="hlt">environment</span> and under a controlled-atmosphere. LDA has a poor ability to classify the storage time of the three <span class="hlt">environments</span> in which litchi was stored. BPNN can effectively recognize the storage time of litchi stored in a refrigerator and a controlled-atmosphere <span class="hlt">environment</span>. However, the BPNN classification of the effect of room temperature storage on litchi was poor. CCA results show a significant correlation between <span class="hlt">electronic</span> nose data and hardness data under the room temperature, and the correlation is more obvious for those under the refrigerator <span class="hlt">environment</span> and controlled-atmosphere <span class="hlt">environment</span>. The BPNN-PLSR can effectively predict the hardness of litchi under refrigerator storage conditions and a controlled-atmosphere <span class="hlt">environment</span>. However, the BPNN-PLSR prediction of the effect of room temperature storage on litchi and global <span class="hlt">environment</span> storage on litchi were poor. Thus, this experiment proved that an <span class="hlt">electronic</span> nose can detect the quality of litchi under refrigeratored storage and a controlled-atmosphere <span class="hlt">environment</span>. These results provide a useful reference for future</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/27338391','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/27338391"><span id="translatedtitle">Quality Detection of Litchi Stored in Different <span class="hlt">Environments</span> Using an <span class="hlt">Electronic</span> Nose.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Xu, Sai; Lü, Enli; Lu, Huazhong; Zhou, Zhiyan; Wang, Yu; Yang, Jing; Wang, Yajuan</p> <p>2016-06-08</p> <p>The purpose of this paper was to explore the utility of an <span class="hlt">electronic</span> nose to detect the quality of litchi fruit stored in different <span class="hlt">environments</span>. In this study, a PEN3 <span class="hlt">electronic</span> nose was adopted to test the storage time and hardness of litchi that were stored in three different types of <span class="hlt">environment</span> (room temperature, refrigerator and controlled-atmosphere). After acquiring data about the hardness of the sample and from the <span class="hlt">electronic</span> nose, linear discriminant analysis (LDA), canonical correlation analysis (CCA), BP neural network (BPNN) and BP neural network-partial least squares regression (BPNN-PLSR), were employed for data processing. The experimental results showed that the hardness of litchi fruits stored in all three <span class="hlt">environments</span> decreased during storage. The litchi stored at room temperature had the fastest rate of decrease in hardness, followed by those stored in a refrigerator <span class="hlt">environment</span> and under a controlled-atmosphere. LDA has a poor ability to classify the storage time of the three <span class="hlt">environments</span> in which litchi was stored. BPNN can effectively recognize the storage time of litchi stored in a refrigerator and a controlled-atmosphere <span class="hlt">environment</span>. However, the BPNN classification of the effect of room temperature storage on litchi was poor. CCA results show a significant correlation between <span class="hlt">electronic</span> nose data and hardness data under the room temperature, and the correlation is more obvious for those under the refrigerator <span class="hlt">environment</span> and controlled-atmosphere <span class="hlt">environment</span>. The BPNN-PLSR can effectively predict the hardness of litchi under refrigerator storage conditions and a controlled-atmosphere <span class="hlt">environment</span>. However, the BPNN-PLSR prediction of the effect of room temperature storage on litchi and global <span class="hlt">environment</span> storage on litchi were poor. Thus, this experiment proved that an <span class="hlt">electronic</span> nose can detect the quality of litchi under refrigeratored storage and a controlled-atmosphere <span class="hlt">environment</span>. These results provide a useful reference for future</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2006PhRvL..96j5007G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2006PhRvL..96j5007G"><span id="translatedtitle">Analysis of Bifurcation Phenomena in the <span class="hlt">Electron</span> Internal <span class="hlt">Transport</span> Barrier in the Large Helical Device</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>García, J.; Yamazaki, K.; Dies, J.; Izquierdo, J.</p> <p>2006-03-01</p> <p>The <span class="hlt">electron</span> internal <span class="hlt">transport</span> barrier (eITB) formation in the Large Helical Device (LHD) is studied with the <span class="hlt">transport</span> code TOTAL and a GyroBohm-like model. The reduction of anomalous <span class="hlt">transport</span> by the E×B shear has been introduced by means of the factor [1+(τωE×B)γ]-1. Simulation results show a clear critical transition between plasma regimes with rather flat <span class="hlt">electron</span> temperature profiles (non-eITB) to a steeped one (with eITB) when average density is low enough. With the aim of studying the eITB formation as a phase transition phenomenon, the <span class="hlt">electron</span> average density is taken as the control parameter and the E×B shearing rate as the order parameter. Results show how the eITB formation in LHD is compatible with a continuum phase transition with critical exponent β=0.40.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/26932777','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/26932777"><span id="translatedtitle">A composite nanostructured <span class="hlt">electron-transport</span> layer for stable hole-conductor free perovskite solar cells: design and characterization.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Yu, Zhenhua; Qi, Fei; Liu, Pei; You, Sujian; Kondamareddy, Kiran Kumar; Wang, Changlei; Cheng, Nian; Bai, Sihang; Liu, Wei; Guo, Shishang; Zhao, Xing-zhong</p> <p>2016-03-21</p> <p>A novel composite nanostructured titanium dioxide (TiO2) based <span class="hlt">electron-transport</span> layer (ETL) is designed by combining size blended nanoparticles (SBNP) and nanoarrays (NA) for efficient perovskite solar cell (PSC) applications. The composite nanostructured (SBNP + NA) ETL is successfully employed in hole-conductor free PSCs, there by achieving a stable device with a maximum efficiency of 13.5%. The improvement in the performance is attributed to the better charge <span class="hlt">transport</span> and lower recombination in the SBNP + NA ETL. Despite the stable high efficiency, SBNP + NA ETL based PSCs are advantageous owing to their low cost, ease of all-solution fabrication process in an open <span class="hlt">environment</span> and good reproducibility.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/1048508','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/1048508"><span id="translatedtitle">Adaptations in <span class="hlt">Electronic</span> Structure Calculations in Heterogeneous <span class="hlt">Environments</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Talamudupula, Sai</p> <p>2011-01-01</p> <p>Modern quantum chemistry deals with <span class="hlt">electronic</span> structure calculations of unprecedented complexity and accuracy. They demand full power of high-performance computing and must be in tune with the given architecture for superior e ciency. To make such applications resourceaware, it is desirable to enable their static and dynamic adaptations using some external software (middleware), which may monitor both system availability and application needs, rather than mix science with system-related calls inside the application. The present work investigates scienti c application interlinking with middleware based on the example of the computational chemistry package GAMESS and middleware NICAN. The existing synchronous model is limited by the possible delays due to the middleware processing time under the sustainable runtime system conditions. Proposed asynchronous and hybrid models aim at overcoming this limitation. When linked with NICAN, the fragment molecular orbital (FMO) method is capable of adapting statically and dynamically its fragment scheduling policy based on the computing platform conditions. Signi cant execution time and throughput gains have been obtained due to such static adaptations when the compute nodes have very di erent core counts. Dynamic adaptations are based on the main memory availability at run time. NICAN prompts FMO to postpone scheduling certain fragments, if there is not enough memory for their immediate execution. Hence, FMO may be able to complete the calculations whereas without such adaptations it aborts.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li class="active"><span>24</span></li> <li><a href="#" onclick='return showDiv("page_25");'>25</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_24 --> <div id="page_25" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li><a href="#" onclick='return showDiv("page_24");'>24</a></li> <li class="active"><span>25</span></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="481"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1991JPhy1...1..837L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1991JPhy1...1..837L"><span id="translatedtitle">Linear <span class="hlt">electronic</span> <span class="hlt">transport</span> in dense plasmas. II. Finite degeneracy contributions</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Léger, D.; Deutsch, C.</p> <p>1991-06-01</p> <p>The formalism described in the first paper in this series is hereafter specialized to a thorough investigation of finite degeneracy contributions to thermoelectronic and mechanical <span class="hlt">transport</span> coefficients, conveniently expressed as reduced quantities. Temperature corrections are systematically discussed through the analytical properties of the jellium dielectric function. The Thomas-Fermi one appears as a paradigm of regular behavior at q=2k_F while the Lindhard and its T-dependent extension head a singular class characterized by diverging derivatives. Specific methods are developed for these important cases. Results are presented in terms of analytic expansions in the degeneracy parameter α, and exact expressions for the above-mentioned corrections are derived up to order α2. Finally we display a number of numerical results pertaining to fully ionized proton-helium binary mixtures of Astrophysical interest. The connection of the present formalism and its numerical outputs with other previous treatments is also carefully examined. Le formalisme exposé et détaillé dans le premier article de cette série est ici appliqué à la détermination des contributions de dégénérescence partielle aux coefficients de <span class="hlt">transport</span> thermoélectroniques et mécanique (viscosité), coefficients préalablement exprimés sous forme d'expressions réduites. Les corrections de température finie sont systématiquement analysées en relation avec les propriétés analytiques de la fonction diélectrique du jellium. Alors que celle de Thomas-Fermi fournit l'exemple type de fonction parfaitement régulière en q=2k_F, celle de Lindhard et sa généralisation à T finie sont au contraire caractérisées par des dérivées divergentes en ce point. Des méthodes spécifiques sont développées pour traiter correctement ces cas importants. Nos résultats sont présentés sous forme de développements analytiques en puissance du paramètre de dégénérescence α, et des expressions</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4463002','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4463002"><span id="translatedtitle">Microbial <span class="hlt">electron</span> <span class="hlt">transport</span> and energy conservation – the foundation for optimizing bioelectrochemical systems</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Kracke, Frauke; Vassilev, Igor; Krömer, Jens O.</p> <p>2015-01-01</p> <p>Microbial electrochemical techniques describe a variety of emerging technologies that use electrode–bacteria interactions for biotechnology applications including the production of electricity, waste and wastewater treatment, bioremediation and the production of valuable products. Central in each application is the ability of the microbial catalyst to interact with external <span class="hlt">electron</span> acceptors and/or donors and its metabolic properties that enable the combination of <span class="hlt">electron</span> <span class="hlt">transport</span> and carbon metabolism. And here also lies the key challenge. A wide range of microbes has been discovered to be able to exchange <span class="hlt">electrons</span> with solid surfaces or mediators but only a few have been studied in depth. Especially <span class="hlt">electron</span> transfer mechanisms from cathodes towards the microbial organism are poorly understood but are essential for many applications such as microbial electrosynthesis. We analyze the different <span class="hlt">electron</span> <span class="hlt">transport</span> chains that nature offers for organisms such as metal respiring bacteria and acetogens, but also standard biotechnological organisms currently used in bio-production. Special focus lies on the essential connection of redox and energy metabolism, which is often ignored when studying bioelectrochemical systems. The possibility of extracellular <span class="hlt">electron</span> exchange at different points in each organism is discussed regarding required redox potentials and effect on cellular redox and energy levels. Key compounds such as <span class="hlt">electron</span> carriers (e.g., cytochromes, ferredoxin, quinones, flavins) are identified and analyzed regarding their possible role in electrode–microbe interactions. This work summarizes our current knowledge on <span class="hlt">electron</span> <span class="hlt">transport</span> processes and uses a theoretical approach to predict the impact of different modes of transfer on the energy metabolism. As such it adds an important piece of fundamental understanding of microbial <span class="hlt">electron</span> <span class="hlt">transport</span> possibilities to the research community and will help to optimize and advance bioelectrochemical</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/26124754','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/26124754"><span id="translatedtitle">Microbial <span class="hlt">electron</span> <span class="hlt">transport</span> and energy conservation - the foundation for optimizing bioelectrochemical systems.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Kracke, Frauke; Vassilev, Igor; Krömer, Jens O</p> <p>2015-01-01</p> <p>Microbial electrochemical techniques describe a variety of emerging technologies that use electrode-bacteria interactions for biotechnology applications including the production of electricity, waste and wastewater treatment, bioremediation and the production of valuable products. Central in each application is the ability of the microbial catalyst to interact with external <span class="hlt">electron</span> acceptors and/or donors and its metabolic properties that enable the combination of <span class="hlt">electron</span> <span class="hlt">transport</span> and carbon metabolism. And here also lies the key challenge. A wide range of microbes has been discovered to be able to exchange <span class="hlt">electrons</span> with solid surfaces or mediators but only a few have been studied in depth. Especially <span class="hlt">electron</span> transfer mechanisms from cathodes towards the microbial organism are poorly understood but are essential for many applications such as microbial electrosynthesis. We analyze the different <span class="hlt">electron</span> <span class="hlt">transport</span> chains that nature offers for organisms such as metal respiring bacteria and acetogens, but also standard biotechnological organisms currently used in bio-production. Special focus lies on the essential connection of redox and energy metabolism, which is often ignored when studying bioelectrochemical systems. The possibility of extracellular <span class="hlt">electron</span> exchange at different points in each organism is discussed regarding required redox potentials and effect on cellular redox and energy levels. Key compounds such as <span class="hlt">electron</span> carriers (e.g., cytochromes, ferredoxin, quinones, flavins) are identified and analyzed regarding their possible role in electrode-microbe interactions. This work summarizes our current knowledge on <span class="hlt">electron</span> <span class="hlt">transport</span> processes and uses a theoretical approach to predict the impact of different modes of transfer on the energy metabolism. As such it adds an important piece of fundamental understanding of microbial <span class="hlt">electron</span> <span class="hlt">transport</span> possibilities to the research community and will help to optimize and advance bioelectrochemical</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017PhR...669....1C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017PhR...669....1C"><span id="translatedtitle">Single-<span class="hlt">electron</span> <span class="hlt">transport</span> in graphene-like nanostructures</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Chiu, Kuei-Lin; Xu, Yang</p> <p>2017-01-01</p> <p>Two-dimensional (2D) materials for their versatile band structures and strictly 2D nature have attracted considerable attention over the past decade. Graphene is a robust material for spintronics owing to its weak spin-orbit and hyperfine interactions, while monolayer transition metal dichalcogenides (TMDs) possess a Zeeman effect-like band splitting in which the spin and valley degrees of freedom are nondegenerate. The surface states of topological insulators (TIs) exhibit a spin-momentum locking that opens up the possibility of controlling the spin degree of freedom in the absence of an external magnetic field. Nanostructures made of these materials are also viable for use in quantum computing applications involving the superposition and entanglement of individual charge and spin quanta. In this article, we review a selection of <span class="hlt">transport</span> studies addressing the confinement and manipulation of charges in nanostructures fabricated from various 2D materials. We supply the entry-level knowledge for this field by first introducing the fundamental properties of 2D bulk materials followed by the theoretical background relevant to the physics of nanostructures. Subsequently, a historical review of experimental development in this field is presented, from the early demonstration of graphene nanodevices on SiO2 substrate to more recent progress in utilizing hexagonal boron nitride to reduce substrate disorder. In the second part of this article, we extend our discussion to TMDs and TI nanostructures. We aim to outline the current challenges and suggest how future work will be geared towards developing spin qubits in 2D materials.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/28230222','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/28230222"><span id="translatedtitle">Conceptual density functional theory for <span class="hlt">electron</span> transfer and <span class="hlt">transport</span> in mesoscopic systems.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Bueno, Paulo R; Miranda, David A</p> <p>2017-02-22</p> <p>Molecular and supramolecular systems are essentially mesoscopic in character. The <span class="hlt">electron</span> self-exchange, in the case of energy fluctuations, or <span class="hlt">electron</span> transfer/<span class="hlt">transport</span>, in the case of the presence of an externally driven electrochemical potential, between mesoscopic sites is energetically driven in such a manner where the electrochemical capacitance (C[small mu, Greek, macron]) is fundamental. Thus, the <span class="hlt">electron</span> transfer/<span class="hlt">transport</span> through channels connecting two distinct energetic (ΔE[small mu, Greek, macron]) and spatially separated mesoscopic sites is capacitively modulated. Remarkably, the relationship between the quantum conductance (G) and the standard electrochemical rate constant (kr), which is indispensable to understanding the physical and chemical characteristics governing <span class="hlt">electron</span> exchange in molecular scale systems, was revealed to be related to C[small mu, Greek, macron], that is, C[small mu, Greek, macron] = G/kr. Accordingly, C[small mu, Greek, macron] is the proportional missing term that controls the <span class="hlt">electron</span> transfer/<span class="hlt">transport</span> in mesoscopic systems in a wide-range, and equally it can be understood from first principles density functional quantum mechanical approaches. Indeed the differences in energy between states is calculated (or experimentally accessed) throughout the electrochemical capacitance as ΔE[small mu, Greek, macron] = β/C[small mu, Greek, macron], and thus constitutes the driving force for G and/or kr, where β is only a proportional constant that includes the square of the unit <span class="hlt">electron</span> charge times the square of the number of <span class="hlt">electron</span> particles interchanged.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/10714274','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/10714274"><span id="translatedtitle">Bioflavonoid effects on the mitochondrial respiratory <span class="hlt">electron</span> <span class="hlt">transport</span> chain and cytochrome c redox state.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Moini, H; Arroyo, A; Vaya, J; Packer, L</p> <p>1999-01-01</p> <p>The polyphenolic structure common to flavonoids enables them to donate <span class="hlt">electrons</span> and exert antioxidant activity. Since the mitochondrial <span class="hlt">electron</span> <span class="hlt">transport</span> chain consists of a series of redox intermediates, the effect of flavonoids in a complex mixture of polyphenols, as well as related pure flavonoids, was evaluated on the rat liver mitochondrial <span class="hlt">electron</span> <span class="hlt">transport</span> chain. A French maritime pine bark extract (PBE), a complex mixture of polyphenols and related pure flavonoids, was able to reduce cytochrome c reversibly, possibly by donation of <span class="hlt">electrons</span> to the iron of the heme group; the donated <span class="hlt">electrons</span> can be utilized by cytochrome c oxidase. Among single flavonoids tested, (-)-epicatechin gallate had the greatest ability to reduce cytochrome c. In addition, PBE competitively inhibited <span class="hlt">electron</span> chain activity in both whole mitochondria and submitochondrial particles. A 3.5-fold increase in the apparent Km value for succinate was calculated from reciprocal plots. Among the flavonoids tested, taxifolin and (-)-epicatechin gallate showed minor inhibitory effects, while (+/-)-catechin and (+)-epicatechin were ineffective. Activities of NADH-ubiquinone, succinate-ubiquinone, and ubiquinol-cytochrome c reductases were inhibited by low concentrations of PBE to a similar extent. However, inhibition of cytochrome c oxidase activity required 4-fold higher PBE concentrations. These results suggest that flavonoids reduce cytochrome c and that PBE inhibits <span class="hlt">electron</span> <span class="hlt">transport</span> chain activity mainly through NADH-ubiquinone, succinate-ubiquinone, and ubiquinol-cytochrome c reductases.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/1345509','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/1345509"><span id="translatedtitle"><span class="hlt">Electron</span> temperature critical gradient and <span class="hlt">transport</span> stiffness in DIII-D</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Smith, Sterling P.; Petty, Clinton C.; White, Anne E.; Holland, Christopher; Bravenec, Ronald; Austin, Max E.; Zeng, Lei; Meneghini, Orso</p> <p>2015-07-06</p> <p>The <span class="hlt">electron</span> energy flux has been probed as a function of <span class="hlt">electron</span> temperature gradient on the DIII-D tokamak, in a continuing effort to validate turbulent <span class="hlt">transport</span> models. In the scan of gradient, a critical <span class="hlt">electron</span> temperature gradient has been found in the <span class="hlt">electron</span> heat fluxes and stiffness at various radii in L-mode plasmas. The TGLF reduced turbulent <span class="hlt">transport</span> model [G.M. Staebler et al, Phys. Plasmas 14, 055909 (2007)] and full gyrokinetic GYRO model [J. Candy and R.E. Waltz, J. Comput. Phys. 186, 545 (2003)] recover the general trend of increasing <span class="hlt">electron</span> energy flux with increasing <span class="hlt">electron</span> temperature gradient scale length, but they do not predict the absolute level of <span class="hlt">transport</span> at all radii and gradients. Comparing the experimental observations of incremental (heat pulse) diffusivity and stiffness to the models’ reveals that TGLF reproduces the trends in increasing diffusivity and stiffness with increasing <span class="hlt">electron</span> temperature gradient scale length with a critical gradient behavior. Furthermore, the critical gradient of TGLF is found to have a dependence on q<sub>95</sub>, contrary to the independence of the experimental critical gradient from q<sub>95</sub>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/pages/biblio/1345509-electron-temperature-critical-gradient-transport-stiffness-diii','SCIGOV-DOEP'); return false;" href="https://www.osti.gov/pages/biblio/1345509-electron-temperature-critical-gradient-transport-stiffness-diii"><span id="translatedtitle"><span class="hlt">Electron</span> temperature critical gradient and <span class="hlt">transport</span> stiffness in DIII-D</span></a></p> <p><a target="_blank" href="http://www.osti.gov/pages">DOE PAGES</a></p> <p>Smith, Sterling P.; Petty, Clinton C.; White, Anne E.; ...</p> <p>2015-07-06</p> <p>The <span class="hlt">electron</span> energy flux has been probed as a function of <span class="hlt">electron</span> temperature gradient on the DIII-D tokamak, in a continuing effort to validate turbulent <span class="hlt">transport</span> models. In the scan of gradient, a critical <span class="hlt">electron</span> temperature gradient has been found in the <span class="hlt">electron</span> heat fluxes and stiffness at various radii in L-mode plasmas. The TGLF reduced turbulent <span class="hlt">transport</span> model [G.M. Staebler et al, Phys. Plasmas 14, 055909 (2007)] and full gyrokinetic GYRO model [J. Candy and R.E. Waltz, J. Comput. Phys. 186, 545 (2003)] recover the general trend of increasing <span class="hlt">electron</span> energy flux with increasing <span class="hlt">electron</span> temperature gradient scale length,more » but they do not predict the absolute level of <span class="hlt">transport</span> at all radii and gradients. Comparing the experimental observations of incremental (heat pulse) diffusivity and stiffness to the models’ reveals that TGLF reproduces the trends in increasing diffusivity and stiffness with increasing <span class="hlt">electron</span> temperature gradient scale length with a critical gradient behavior. Furthermore, the critical gradient of TGLF is found to have a dependence on q95, contrary to the independence of the experimental critical gradient from q95.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/21867317','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/21867317"><span id="translatedtitle">Effect of the plasma-generated magnetic field on relativistic <span class="hlt">electron</span> <span class="hlt">transport</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Nicolaï, Ph; Feugeas, J-L; Regan, C; Olazabal-Loumé, M; Breil, J; Dubroca, B; Morreeuw, J-P; Tikhonchuk, V</p> <p>2011-07-01</p> <p>In the fast-ignition scheme, relativistic <span class="hlt">electrons</span> <span class="hlt">transport</span> energy from the laser deposition zone to the dense part of the target where the fusion reactions can be ignited. The magnetic fields and <span class="hlt">electron</span> collisions play an important role in the collimation or defocusing of this <span class="hlt">electron</span> beam. Detailed description of these effects requires large-scale kinetic calculations and is limited to short time intervals. In this paper, a reduced kinetic model of fast <span class="hlt">electron</span> <span class="hlt">transport</span> coupled to the radiation hydrodynamic code is presented. It opens the possibility to carry on hybrid simulations in a time scale of tens of picoseconds or more. It is shown with this code that plasma-generated magnetic fields induced by noncollinear temperature and density gradients may strongly modify <span class="hlt">electron</span> <span class="hlt">transport</span> in a time scale of a few picoseconds. These fields tend to defocus the <span class="hlt">electron</span> beam, reducing the coupling efficiency to the target. This effect, that was not seen before in shorter time simulations, has to be accounted for in any ignition design using <span class="hlt">electrons</span> as a driver.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/20931122','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/20931122"><span id="translatedtitle">Characteristics and <span class="hlt">transport</span> of organochlorine pesticides in urban <span class="hlt">environment</span>: air, dust, rain, canopy throughfall, and runoff.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Zhang, Wei; Ye, Youbin; Hu, Dan; Ou, Langbo; Wang, Xuejun</p> <p>2010-11-01</p> <p>Characteristics and <span class="hlt">transport</span> of organochlorine pesticides (OCPs) in urban multiple <span class="hlt">environments</span>, including air, dust, rain, canopy throughfall, and runoff water, are explored in this study. Hexachlorocyclohexanes (HCHs) dominated in both air and rain water, and dichlorodiphenyltrichloroethane (DDT) related substances showed a higher affinity to dust. Relatively high concentrations of DDT and dichlorodiphenyldichloroethylene (DDE) in air, rain and dust imply that technical DDT in the <span class="hlt">environment</span> has been degrading, and there may be unknown local or regional emission sources that contain DDTs in the study area. Source identification showed that DDTs in Beijing urban <span class="hlt">environments</span> with a fresh signature may originate from the atmospheric <span class="hlt">transport</span> from remote areas. The ratio of α-/γ-HCH in dust, rain, canopy throughfall and runoff were close to 1, indicating the possible use of lindane. OCPs in runoff were <span class="hlt">transported</span> from various sources including rain, dust, and canopy throughfall. In runoff, DDTs and hexachlorobenzene (HCB) were mainly <span class="hlt">transported</span> from dust, and HCHs were mainly from rain and canopy throughfall.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=1056728','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=1056728"><span id="translatedtitle">High-Temperature Sensitivity and Its Acclimation for Photosynthetic <span class="hlt">Electron</span> <span class="hlt">Transport</span> Reactions of Desert Succulents 1</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Chetti, Mahadev B.; Nobel, Park S.</p> <p>1987-01-01</p> <p>Photosynthetic <span class="hlt">electron</span> <span class="hlt">transport</span> reactions of succulent plants from hot deserts are able to tolerate extremely high temperatures and to acclimate to seasonal increases in temperature. In this study, we report the influence of relatively long, in vivo, high-temperature treatments on <span class="hlt">electron</span> <span class="hlt">transport</span> reactions for two desert succulents, Agave deserti and Opuntia ficus-indica, species which can tolerate 60°C. Whole chain <span class="hlt">electron</span> <span class="hlt">transport</span> averaged 3°C more sensitive to a 1-hour high-temperature treatment than did PSII (Photosystem II) which in turn averaged 3°C more sensitive than did PSI. For plants maintained at day/night air temperatures of 30°C/20°C, treatment at 50°C caused these reactions to be inhibited an average of 39% during the first hour, an additional 31% during the next 4 hours, and 100% by 12 hours. Upon shifting the plants from 30°C/20°C to 45°C/35°C, the high temperatures where activity was inhibited 50% increased 3°C to 8°C for the three <span class="hlt">electron</span> <span class="hlt">transport</span> reactions, the half-times for acclimation averaging 5 days for A. deserti and 4 days for O. ficus-indica. For the 45°C/35°C plants treated at 60°C for 1 hour, PSI activity was reduced by 54% for A. deserti and 36% for O. ficus-indica. Acclimation leads to a toleration of very high temperatures without substantial disruption of <span class="hlt">electron</span> <span class="hlt">transport</span> for these desert succulents, facilitating their survival in hot deserts. Indeed, the <span class="hlt">electron</span> <span class="hlt">transport</span> reactions of these species tolerate longer periods at higher temperatures than any other vascular plant so far reported. PMID:16665562</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/16665562','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/16665562"><span id="translatedtitle">High-temperature sensitivity and its acclimation for photosynthetic <span class="hlt">electron</span> <span class="hlt">transport</span> reactions of desert succulents.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Chetti, M B; Nobel, P S</p> <p>1987-08-01</p> <p>Photosynthetic <span class="hlt">electron</span> <span class="hlt">transport</span> reactions of succulent plants from hot deserts are able to tolerate extremely high temperatures and to acclimate to seasonal increases in temperature. In this study, we report the influence of relatively long, in vivo, high-temperature treatments on <span class="hlt">electron</span> <span class="hlt">transport</span> reactions for two desert succulents, Agave deserti and Opuntia ficus-indica, species which can tolerate 60 degrees C. Whole chain <span class="hlt">electron</span> <span class="hlt">transport</span> averaged 3 degrees C more sensitive to a 1-hour high-temperature treatment than did PSII (Photosystem II) which in turn averaged 3 degrees C more sensitive than did PSI. For plants maintained at day/night air temperatures of 30 degrees C/20 degrees C, treatment at 50 degrees C caused these reactions to be inhibited an average of 39% during the first hour, an additional 31% during the next 4 hours, and 100% by 12 hours. Upon shifting the plants from 30 degrees C/20 degrees C to 45 degrees C/35 degrees C, the high temperatures where activity was inhibited 50% increased 3 degrees C to 8 degrees C for the three <span class="hlt">electron</span> <span class="hlt">transport</span> reactions, the half-times for acclimation averaging 5 days for A. deserti and 4 days for O. ficus-indica. For the 45 degrees C/35 degrees C plants treated at 60 degrees C for 1 hour, PSI activity was reduced by 54% for A. deserti and 36% for O. ficus-indica. Acclimation leads to a toleration of very high temperatures without substantial disruption of <span class="hlt">electron</span> <span class="hlt">transport</span> for these desert succulents, facilitating their survival in hot deserts. Indeed, the <span class="hlt">electron</span> <span class="hlt">transport</span> reactions of these species tolerate longer periods at higher temperatures than any other vascular plant so far reported.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/25608276','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/25608276"><span id="translatedtitle">Correlation of <span class="hlt">electron</span> <span class="hlt">transport</span> and photocatalysis of nanocrystalline clusters studied by Monte-Carlo continuity random walking.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Liu, Baoshun; Li, Ziqiang; Zhao, Xiujian</p> <p>2015-02-21</p> <p>In this research, Monte-Carlo Continuity Random Walking (MC-RW) model was used to study the relation between <span class="hlt">electron</span> <span class="hlt">transport</span> and photocatalysis of nano-crystalline (nc) clusters. The effects of defect energy disorder, spatial disorder of material structure, <span class="hlt">electron</span> density, and interfacial transfer/recombination on the <span class="hlt">electron</span> <span class="hlt">transport</span> and the photocatalysis were studied. Photocatalytic activity is defined as 1/τ from a statistical viewpoint with τ being the <span class="hlt">electron</span> average lifetime. Based on the MC-RW simulation, a clear physical and chemical "picture" was given for the photocatalytic kinetic analysis of nc-clusters. It is shown that the increase of defect energy disorder and material spatial structural disorder, such as the decrease of defect trap number, the increase of crystallinity, the increase of particle size, and the increase of inter-particle connection, can enhance photocatalytic activity through increasing <span class="hlt">electron</span> <span class="hlt">transport</span> ability. The increase of <span class="hlt">electron</span> density increases the <span class="hlt">electron</span> Fermi level, which decreases the activation energy for <span class="hlt">electron</span> de-trapping from traps to extending states, and correspondingly increases <span class="hlt">electron</span> <span class="hlt">transport</span> ability and photocatalytic activity. Reducing recombination of <span class="hlt">electrons</span> and holes can increase <span class="hlt">electron</span> <span class="hlt">transport</span> through the increase of <span class="hlt">electron</span> density and then increases the photocatalytic activity. In addition to the <span class="hlt">electron</span> <span class="hlt">transport</span>, the increase of probability for <span class="hlt">electrons</span> to undergo photocatalysis can increase photocatalytic activity through the increase of the <span class="hlt">electron</span> interfacial transfer speed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/2825979','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/2825979"><span id="translatedtitle">Proton stoichiometry of <span class="hlt">electron</span> <span class="hlt">transport</span> in rodent tumor mitoplasts.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Ferreira, J; Reynafarje, B; Costa, L E; Lehninger, A L</p> <p>1988-02-01</p> <p>The mechanistic vectorial H+/O translocation ratios characteristic of energy-conserving sites 2 + 3 and site 3 of the respiratory chain of two tumor cell lines were determined using succinate and ferrocytochrome c, respectively, as <span class="hlt">electron</span> donors. The measurements were carried out on mitoplasts in order to allow ferrocytochrome c free access to its binding site on the inner mitochondrial membrane. The tumor cell lines used were Ehrlich ascites tumor and the AS30-D ascites tumor. K+ was used as charge-compensating cation in the presence of valinomycin. The O2 uptake rate measurements were made with a fast-responding membrane-less electrode whose response time was closely matched with that of a pH electrode. The rates of O2 uptake and H+ ejection during the apparent zero-order rate phase of respiration, analyzed by computer, were extrapolated to zero time. The observed H+/O ratios for succinate oxidation in both tumors exceeded 7 and approached 8 and the H+/O ratios for the cytochrome oxidase reaction closely approached 4.0, in agreement with data or normal mitochondria. However, the rates of H+ back decay in the tumor mitochondria are relatively high and may influence the net efficiency of oxidative phosphorylation under intracellular conditions.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013PhDT.......123P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013PhDT.......123P"><span id="translatedtitle">Temperature-dependent <span class="hlt">electron</span> <span class="hlt">transport</span> in quantum dot photovoltaics</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Padilla, Derek J.</p> <p></p> <p>Quantum dot photovoltaics have attracted much interest from researchers in recent years. They have the potential to address both costs and efficiencies of solar cells while simultaneously demonstrating novel physics. Thin-film devices inherently require less material than bulk crystalline silicon, and solution deposition removes the high energy used in fabrication processes. The ease of bandgap tunability in quantum dots through size control allows for simple graded bandgap structures, which is one method of breaking beyond the Shockley-Queisser limit. Power output can also be increased through the process of multiple exciton generation, whereby more than one <span class="hlt">electron</span> participates in conduction after the absorption of a single photon. In this dissertation work, quantum dot photovoltaics are examined through a range of temperatures. Exploring the current-voltage-temperature parameter space provides insight into the dominant conduction mechanisms within these materials, which is largely not agreed upon. Beginning with PbS quantum dots, changes in device structure are examined by varying the capping ligand and nanoparticle size. This leads similar studies of new, germanium quantum dot devices. Through this understanding, further optimization of device structure can lead to enhanced device performance.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/22086022','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/22086022"><span id="translatedtitle">Effects of parallel <span class="hlt">electron</span> dynamics on plasma blob <span class="hlt">transport</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Angus, Justin R.; Krasheninnikov, Sergei I.; Umansky, Maxim V.</p> <p>2012-08-15</p> <p>The 3D effects on sheath connected plasma blobs that result from parallel <span class="hlt">electron</span> dynamics are studied by allowing for the variation of blob density and potential along the magnetic field line and using collisional Ohm's law to model the parallel current density. The parallel current density from linear sheath theory, typically used in the 2D model, is implemented as parallel boundary conditions. This model includes electrostatic 3D effects, such as resistive drift waves and blob spinning, while retaining all of the fundamental 2D physics of sheath connected plasma blobs. If the growth time of unstable drift waves is comparable to the 2D advection time scale of the blob, then the blob's density gradient will be depleted resulting in a much more diffusive blob with little radial motion. Furthermore, blob profiles that are initially varying along the field line drive the potential to a Boltzmann relation that spins the blob and thereby acts as an addition sink of the 2D potential. Basic dimensionless parameters are presented to estimate the relative importance of these two 3D effects. The deviation of blob dynamics from that predicted by 2D theory in the appropriate limits of these parameters is demonstrated by a direct comparison of 2D and 3D seeded blob simulations.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=207228','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=207228"><span id="translatedtitle">Metronidazole activation and isolation of Clostridium acetobutylicum <span class="hlt">electron</span> <span class="hlt">transport</span> genes.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Santangelo, J D; Jones, D T; Woods, D R</p> <p>1991-01-01</p> <p>An Escherichia coli F19 recA, nitrate reductase-deficient mutant was constructed by transposon mutagenesis and shown to be resistant to metronidazole. This mutant was a most suitable host for the isolation of Clostridium acetobutylicum genes on recombinant plasmids, which activated metronidazole and rendered the E. coli F19 strain sensitive to metronidazole. Twenty-five E. coli F19 clones containing different recombinant plasmids were isolated and classified into five groups on the basis of their sensitivity to metronidazole. The clones were tested for nitrate reductase, pyruvate-ferredoxin oxidoreductase, and hydrogenase activities. DNA hybridization and restriction endonuclease mapping revealed that four of the C. acetobutylicum insert DNA fragments on recombinant plasmids were linked in an 11.1-kb chromosomal fragment. DNA sequencing and amino acid homology studies indicated that this DNA fragment contained a flavodoxin gene which encoded a protein of 160 amino acids that activated metronidazole and made the E. coli F19 mutant very sensitive to metronidazole. The flavodoxin and hydrogenase genes which are involved in <span class="hlt">electron</span> transfer systems were linked on the 11.1-kb DNA fragment from C. acetobutylicum. Images PMID:1991710</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015JAP...117o4504R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015JAP...117o4504R"><span id="translatedtitle">Vertical <span class="hlt">electron</span> <span class="hlt">transport</span> in van der Waals heterostructures with graphene layers</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ryzhii, V.; Otsuji, T.; Ryzhii, M.; Aleshkin, V. Ya.; Dubinov, A. A.; Mitin, V.; Shur, M. S.</p> <p>2015-04-01</p> <p>We propose and analyze an analytical model for the self-consistent description of the vertical <span class="hlt">electron</span> <span class="hlt">transport</span> in van der Waals graphene-layer (GL) heterostructures with the GLs separated by the barriers layers. The top and bottom GLs serve as the structure emitter and collector. The vertical <span class="hlt">electron</span> <span class="hlt">transport</span> in such structures is associated with the propagation of the <span class="hlt">electrons</span> thermionically emitted from GLs above the inter-GL barriers. The model under consideration describes the processes of the <span class="hlt">electron</span> thermionic emission from and the <span class="hlt">electron</span> capture to GLs. It accounts for the nonuniformity of the self-consistent electric field governed by the Poisson equation which accounts for the variation of the <span class="hlt">electron</span> population in GLs. The model takes also under consideration the cooling of <span class="hlt">electrons</span> in the emitter layer due to the Peltier effect. We find the spatial distributions of the electric field and potential with the high-electric-field domain near the emitter GL in the GL heterostructures with different numbers of GLs. Using the obtained spatial distributions of the electric field, we calculate the current-voltage characteristics. We demonstrate that the Peltier cooling of the two-dimensional <span class="hlt">electron</span> gas in the emitter GL can strongly affect the current-voltage characteristics resulting in their saturation. The obtained results can be important for the optimization of the hot-<span class="hlt">electron</span> bolometric terahertz detectors and different devices based on GL heterostructures.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/25631449','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/25631449"><span id="translatedtitle">Effects of <span class="hlt">electron</span> correlations on <span class="hlt">transport</span> properties of iron at Earth's core conditions.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Zhang, Peng; Cohen, R E; Haule, K</p> <p>2015-01-29</p> <p>Earth's magnetic field has been thought to arise from thermal convection of molten iron alloy in the outer core, but recent density functional theory calculations have suggested that the conductivity of iron is too high to support thermal convection, resulting in the investigation of chemically driven convection. These calculations for resistivity were based on <span class="hlt">electron</span>-phonon scattering. Here we apply self-consistent density functional theory plus dynamical mean-field theory (DFT + DMFT) to iron and find that at high temperatures <span class="hlt">electron-electron</span> scattering is comparable to the <span class="hlt">electron</span>-phonon scattering, bringing theory into agreement with experiments and solving the <span class="hlt">transport</span> problem in Earth's core. The conventional thermal dynamo picture is safe. We find that <span class="hlt">electron-electron</span> scattering of d <span class="hlt">electrons</span> is important at high temperatures in transition metals, in contrast to textbook analyses since Mott, and that 4s <span class="hlt">electron</span> contributions to <span class="hlt">transport</span> are negligible, in contrast to numerous models used for over fifty years. The DFT+DMFT method should be applicable to other high-temperature systems where <span class="hlt">electron</span> correlations are important.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/22402879','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/22402879"><span id="translatedtitle">Vertical <span class="hlt">electron</span> <span class="hlt">transport</span> in van der Waals heterostructures with graphene layers</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Ryzhii, V.; Otsuji, T.; Ryzhii, M.; Aleshkin, V. Ya.; Dubinov, A. A.; Mitin, V.; Shur, M. S.</p> <p>2015-04-21</p> <p>We propose and analyze an analytical model for the self-consistent description of the vertical <span class="hlt">electron</span> <span class="hlt">transport</span> in van der Waals graphene-layer (GL) heterostructures with the GLs separated by the barriers layers. The top and bottom GLs serve as the structure emitter and collector. The vertical <span class="hlt">electron</span> <span class="hlt">transport</span> in such structures is associated with the propagation of the <span class="hlt">electrons</span> thermionically emitted from GLs above the inter-GL barriers. The model under consideration describes the processes of the <span class="hlt">electron</span> thermionic emission from and the <span class="hlt">electron</span> capture to GLs. It accounts for the nonuniformity of the self-consistent electric field governed by the Poisson equation which accounts for the variation of the <span class="hlt">electron</span> population in GLs. The model takes also under consideration the cooling of <span class="hlt">electrons</span> in the emitter layer due to the Peltier effect. We find the spatial distributions of the electric field and potential with the high-electric-field domain near the emitter GL in the GL heterostructures with different numbers of GLs. Using the obtained spatial distributions of the electric field, we calculate the current-voltage characteristics. We demonstrate that the Peltier cooling of the two-dimensional <span class="hlt">electron</span> gas in the emitter GL can strongly affect the current-voltage characteristics resulting in their saturation. The obtained results can be important for the optimization of the hot-<span class="hlt">electron</span> bolometric terahertz detectors and different devices based on GL heterostructures.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li><a href="#" onclick='return showDiv("page_24");'>24</a></li> <li class="active"><span>25</span></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_25 --> <center> <div class="footer-extlink text-muted"><small>Some links on this page may take you to non-federal websites. 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